As I recently explained to someone, a big part of the problem with American elites is that they have been indoctrinated and trained to think more like British and European oligarchs than as American citizens. A century ago, that would have been a very damning, and damaging, indictment to level at someone. Today, I would say the American republic is barely a memory at this point. Americans should be outraged that Rupert Murdoch and his media empire, including Fox News, were never at least forced to register as foreign agents, like RT Television recently was.

The following timeline is very incomplete, but I think, and hope, there is enough here to shock most people, and leave them with a lot of questions. The timeline is taken primarily from:

"British Preparations for War with the North, 1861-1862," by Kenneth Bourne, The English Historical Review, Vol. 76, No. 301 (Oct., 1961), pp. 600-632, available in pdf here.

Clad in Iron: The American Civil War and the Challenge of British Naval Power, by Howard J. Fuller, Praeger, Westport, Conn., 2008

The Cause of All Nations: An International History of the American Civil War, by Don H. Doyle, Basic Books, New York, NY, 2015.

Timeline of British War Preparations Against the United States

24 May 1861 –  British Prime Minister Henry John Temple, Third Viscount Palmerston, writes to Colonial Secretary, the Duke of Newcastle, that PM was increasingly anxious to establish in Canada a force of at least 10,000 regular troops before the winter cut off communications to Canada. Palmerston reiterated this concern in 9 July 1861 letter to Foreign Secretary, Lord John Russell.

17 July 1861 – Mexico’s President Benito Juárez suspended loan-interest payments to foreign countries. U.S. efforts to avert this crisis, and preclude intervention by European powers, resulted in the McLane-Ocampo Treaty, signed in Veracruz 14 December 1859. But the bitter rivalry between northerners and southerners in the U.S. Senate prevented ratification. The McLane-Ocampo Treaty is little known in the U.S. today, but is a well known issue of academic controversy in Mexico, with one side arguing the Treaty shows Juárez was not progressive at all, but sold out to the U.S., ignoring the probability that the U.S. assistance would have probably prevented the following train of events which led to an invasion by European powers, the foreign deposing of Juarez, and the imposition of a European monarch.

2 September 1861 - Captain R. Collinson, Royal Navy surveyor, submitted “Memoranda on the Assistance which can be rendered to the Province of Canada by Her Majesty's Navy in the event of war with the United States” to the Admiralty, listing measures to strengthen the defense of Canada, and stressed in particular the impossibility of keeping the St. Lawrence open once war with the U.S. had begun.

31 October 1861 - France, Britain, and Spain agreed to the Treaty of London, to coordinate the use of force to extract loan repayments from Mexico. This violated the Monroe Doctrine, but the European powers calculated, correctly, that the U.S. government would not be willing to respond appropriately because of the Civil War it was engaged in.

8 November 1861 - USS San Jacinto, commanded by Captain Charles Wilkes, intercepted the British mail packet RMS Trent in international waters between Cuba and the Bahama. The Trent was stopped and boarded, and James Murray Mason and John Slidell, Confederate officials on their way to Britain to serve as diplomats, were arrested and removed to the San Jacinto.

27 November 1861 – News of removal of Mason and Slidell from RMS Trent reaches Britain

29-30 November 1861 – PM Palmerston’s Cabinet met and drafted initial draft to U.S. of demands for satisfaction, including release of Mason and Slidell, apology, and disciplining of US Navy Captain Wilkes

4 December 1861 – British War Office decided to expedite immediate shipping of guns and rifles to Canada which had been delayed by lack of regular transport, and send a small reinforcement of regulars, plus officers and non-commissioned-officers to supervise construction of defense works and expansion of the Canadian militia.

8-17 December 1861 – British, French, and Spanish fleets and troops arrived at Veracruz, Mexico and begin military seizures of towns and facilities. France would land over 38,000 troops and begin a campaign to capture Mexico City and impose a monarchy, with Ferdinand Maximilian, younger brother of the Austrian emperor Francis Joseph I, as “Emperor.” The Roman Catholic Church in Mexico, upper-class conservatives, and some Indian communities accepted and collaborated with the French-imposed monarchy.

8 December 1861 – British War Office decided to increase the force being immediately sent to Canada to four battalions of infantry, three batteries of field artillery and two companies of engineers, about 5,000 men.

9 December 1861 – British War Office decided to double force being sent to 10,000 men.

12 December 1861 to 4 January 1862 - entire force of over 10,500 officers and men, together with arms, artillery and ammunition, and clothing and stores of all kinds, left the British Isles in a variety of ships specially hired for the purpose. The only Admiralty troop transport, RMS Himalaya, was already engaged in delivering forces to Mexico.

14 December 1861 - Commander-in-chief of the British Army, the Duke of Cambridge, sends orders to Commander-in-chief in North America, Lt. General Sir William Fenwick Williams. Immediately upon learning of the outbreak of war with the U.S., Williams is to attack Rouse's Point, New York (where Lake Champlain flows into the Richelieu River, thus one of the key strategic points of the North American continent) and block any attempt by American forces to advance toward Canada.

15 December 1861 - First news of British reaction to boarding of Trent and seizure of Mason and Slidell reached the United States.

15 December 1861 – Secret Royal Navy assessment of vulnerability of U.S. Atlantic coast to attack is circulated in the Admiralty and to Commander of the North American Station, Royal Navy Admiral Sir Alexander Milne. The title says it all: List of the Chief Ports on the Federal Coast of the United States, showing the Shipping, Population, Dockyards and Defences as far as known; also how far accessible or vulnerable to an Attack, as far as can be gathered from the Charts. With an approximate Estimate of the Number of vessels required to Blockade the several Ports and Rivers. Includes latest intelligence on U.S. coastal defense forts and batteries, and specific suggestions for attacking Boston, New York City, and other points. Here is the Google books scan of this frightening document.

17 December 1861 – Final decision in British War Office to add a large increase of garrison artillery to reinforcements being sent to Canada. This would bring the total British troops to nearly 12,500 in Canada and over 5,000 in the Maritime Provinces. Moreover, in case of an unsatisfactory response from the U.S., the War Office began assembling a further force to be held ready to embark.

25 December 1861 - Meeting of Lincoln's cabinet held, with Massachusetts Senator Charles Sumner attending, to consider war with Britain, and how to respond to British demands concerning the Trent. Sumner read personal letters he had received from British Radical members of Parliament John Bright and Richard Cobden, warning of mounting war fever in Britain, and urging a conciliatory response by the U.S. to avoid war.

27 December 1861 – U.S. Secretary of State Seward sends a reply to Britain that grudgingly agreed to release Mason and Slidell to the British.

29 December 1861 – HMS Conqueror, 27 foot draft steam ship-of-the line ran aground and wrecked at Rum Cay, Jamaica. This convinced Admiral Milne, Commander of the North American Station, that deep draft ships of the line were more a liability than an asset for operations along the coast of the western hemisphere.

5 January 1862 – The British ship Melbourne, carrying the staff officers of the force sent to Canada, docked in Halifax. It had left Cork on 14 December but became separated from its convoy in bad weather, began to run out of coal stopped to refuel at Sydney, Cape Breton. Since the the passage of the St. Lawrence was now more dangerous because of ice, and the Melbourne engine's malfunctioning, the staff officers were sent on a mail packet to Boston, “where, having removed the military labels from their baggage, they traveled to Montreal by the Grand Trunk Railway.”

8 January 1862 - U.S. Secretary of State Seward’s reply regarding the Trent reached Britain.

8 March 1862 – the Confederate ironclad CSS Virginia (former USS Merrimack) enters Hampton Roads and easily destroys first-line sailing warships USS Congress and USS Cumberland. It is actually the destruction of these two U.S. Navy ships that makes the Admiralty immediately realize wooden sailing ships--no matter how large and how well armed--have become instantly obsolete.

9 March 1862 – USS Monitor enters Hampton Roads and engages CSS Virginia in battle. The ability of Monitor's turret to accurately revolve and fire was a capability the Royal Navy was working feverishly on, without success. That the Americans had achieved this technology first greatly increased the Admiralty's apprehensions of operating and fighting in U.S. coastal waters. (Another technological breakthrough the Admiralty feared was U.S. Army artillery officer Thomas Jackson Rodman's perfection of casting core-cooled artillery in 1859. Rodman's method of casting removed the metallurgical flaws of traditionally cast guns, allowing castings of guns up to 20-inch bore size. A 15-inch Rodman gun, of which 323 were made during the Civil War, could hurl a 352-pound shell 5,018 yards. By contrast, the Royal Navy's standard 32-pound cannon had an effective range of 1,220 yards.)

10 March 1862 - Milne wrote to First Sea Lord (military commander of the Royal Navy, in contrast to the political First Lord of the Admiralty) Sir Frederick Grey: “If it had been war the great want would have been Frigates and Corvettes.... The Line of Battle ships would never have stood the gales and sea of the American coast. Every one of them would have been disabled, in fact I don’t see of what service I could have employed them. As to attacking Forts it much never be done by anchoring ships but by ships passing and repassing in rotation so as not to allow a steady object to the Enemy. Ships with larger draft of water are unfit for this mode of attack; you need not build any more. Their days are numbered except [against] France…. If she ever gets up a Navy.”

5 May 1862 – Mexican army under General Ignacio Zaragoza defeated the French army in the Battle of Puebla. This halted the French army’s advance on the capital, Mexico City, but only temporarily. But the victory is celebrated today as the Cinco de Mayo holiday.

29 July 1862 - British authorities turn a blind eye to the departure of a specially built commerce raider from the John Laird & Sons Company shipyard near Liverpool. In the Azores, the ship was armed and manned by Confederate sailors to become the CSS Alabama. Over the next two years, she destroyed 65 U.S. vessels and caused 715 more to reflag as British.

17 September 1862 - Union Army victory in Civil War's largest battle to date, Antietam.

22 September 1862 - Lincoln announced to his cabinet meeting his intention to issue the Emancipation Proclamation. By finally unambiguously making the Union's war objective the ending of slavery, support for the Union is solidified among the republican revolutionaries of Europe led by Giuseppe Garibaldi.

3 October 1862 - British newspapers publish a letter from Garibaldi dated 28 September, "To the English Nation." Garibaldi urged the British people to resist the designs of Napoleon III and by implication, their own rulers, to support the United States. "She is, after all, your daughter, risen from your bosom.... Aid her to come out from the terrible struggle in which she is involved by the traffickers in human flesh.... Help her, and then make her sit by your side in the great assembly of nations, the final work of human reason."

3 October 1862 - 80,000 to 100,000 supporters of Garibaldi gather in London's Hyde Park. When they are attacked by men armed with bludgeons, a day-long battle ensues, causing extreme alarm among British rulers.

7 October 1862 – Chancellor of the Exchequer William Gladstone delivered speech in Newcastle upon Tyne: “there is no doubt that Jefferson Davis and other leaders of the South have made an Army; they are making, it appears, a Navy; and they have made what is more than either — they have made a Nation... We may anticipate with certainty the success of the Southern States so far as regards their separation from the North. I cannot but believe that that event is as certain as any event yet and contingent can be.” 

7 October 1862 –  News arrived in Britain of Lincoln's decision to issue the Emancipation Proclamation.

16 October 1862 – British cabinet met to consider intervention in light of news of Union victory at Antietam, and announcement of forthcoming Emancipation Proclamation.

27 October 1862 – Napoleon III proposed to British ambassador in Paris Lord Cowley joint mediation in U.S. Civil War.

27 October 1862 – PM Palmerston wrote to Foreign Minister Russell, complaining of "Scum of the Community" rising in protest. Besides the riot in Hyde Park, there had been a large protest in Birkenhead, where the Laird shipyard was building more commerce raiders for the Confederacy.

October 1862 – French sent iron plated Normandie to Veracruz. Lord Somerset observed, France “could hardly have done this against Mexico, which has no fleet and no fort to be taken.”

22 January 1863 - In Poland, a spontaneous protest by young Poles against conscription into the Imperial Russian Army exploded into a massive uprising that spread to Lithuania, Belarus, Latvia, northern Ukraine and western Russia.

30 April 1863 - Battle of Camarón, in which a French Foreign Legion patrol of 62 soldiers and three officers fought to the death against Mexican infantry and cavalry units numbering three battalions, about 3,000 men. This made the French Foreign Legion France's most famous instrument of empire, and 30 April remains the most important day of celebration for French Legionnaires.

7 June 1863 – French troops occupy Mexico City.