Most Americans forget, or never learned, that McCarthyism actually started with the House Committee on Un-American Activities in 1938. It was formed by Democrats for the purpose of persecuting leftists for their own political benefit.
Joseph McCarthy was just an opportunistic late-comer to the Red Scare who used an existing program of repression and turned it into an out-of-control monster.
History, who so often prefers to repeat herself, is once again clearing her throat.

“The 1980s are now calling to ask for their foreign policy back because the Cold War’s been over for 20 years.”
- President Obama publicly mocking Mitt Romney’s assertion that Russia was America’s “Number One geopolitical foe” in 2012

Not surprisingly, the Democratic-led Neo-McCarthyism began by Hillary supporters smearing Bernie Sanders in the spring.

Meanwhile, Clinton operative David Brock said “Sanders is a socialist” and “has got a 30 year history of affiliation with a lot of whackadoodle ideas and parties,” and pro-Clinton pundits linked Sanders to Communists through his 1980s praise of Castro and the Sandinistas. All of that culminated in Republicans like Lindsey Graham and National Review citing Sanders’ honeymoon in the Soviet Union as proof of his suspicious loyalties:

McCaskill WIELDS A KNIFE: GOP is nice to Bernie because "they can’t wait to run an ad with a hammer and sickle"https://t.co/0TAOcmTnyX

— Jonathan Martin (@jmartNYT) January 20, 2016

Then it was Jill Stein's turn to be smeared.

One Clinton-supporting blog – while also lying by claiming that “she only criticized the US” – attacked Stein for criticizing the U.S. while standing on dirty foreign soil (“with Red Square as her backdrop”), a long-standing trope used by the Far Right to attack liberals and Democrats for being unpatriotic by virtue of criticizing the U.S. while outside its borders. Commenting on that post, numerous Clinton supporters predictably denounced Stein as a traitor, saying “I don’t think it goes too far to suggest these are acts of sedition and possibly treason,” while the blogger himself dismissed objections over his “red-baiting” by saying “Putin is former KGB!” Journalists from major media outlets used all this to announce that Putin now has not one but (at least) two presidential candidates he controls:...
So that’s the Democratic Party’s approach to the 2016 election. Those who question, criticize or are perceived to impede Hillary Clinton’s smooth, entitled path to the White House are vilified as stooges, sympathizers and/or agents of Russia: Trump, WikiLeaks, Sanders, The Intercept, Jill Stein. Other than loyal Clinton supporters, is there anyone left who is not covertly controlled by or in service to The Ruskies?

Creepy @DrJillStein video from Moscow gushing over Russian support for human rights, dinner w Putin, RT anniv party https://t.co/GQ4zihWC6A

— Andrew S. Weiss (@andrewsweiss) August 6, 2016

The Neo-McCarthyism was officially launched this summer by corporate-centrist Democrats with purely short-term goals.

In their zeal to prevent Donald Trump from becoming president—a goal we share—representative voices of the liberal establishment have joined with the forces of neoconservatism to engage in what can only be described as McCarthyist rhetoric....
Over the past month alone, establishment voices like Franklin Foer, Paul Krugman, Jeffrey Goldberg, Josh Marshall, and Jonathan Chait, among others, have Kremlin-baited Trump in lieu of reasoned argument and factual critique. On July 21, The Atlantic’s Goldberg informed readers that “The Republican nominee for president, Donald J. Trump, has chosen this week to unmask himself as a de facto agent of Russian President Vladimir Putin.” Krugman followed this up on July 22 by asking in The New York Times: “If elected, would Donald Trump be Vladimir Putin’s man in the White House?” Krugman then answered his own baseless question: “Mr. Trump would, in office, actually follow a pro-Putin foreign policy, at the expense of America’s allies and her own self-interest.”

The smear campaign extended far beyond Trump and was "used to vilify anyone perceived to be an impediment to Clinton’s victory."
Once you've taken the McCarthyism genie out of the bottle, it's awfully hard to put it back, and Democrats haven't even tried.
In fact, Democrats have doubled-down.

A week ago, when the House approved by a 390-30 margin and sent to the Senate the Intelligence Authorization Act for fiscal 2017, Schiff praised “important provisions aimed at countering Russia’s destabilizing efforts — including those targeting our elections.” One of those “important provisions,” Section 501, sets up in the executive branch “an interagency committee to counter active measures by the Russian Federation to exert covert influence.”
This high-level committee could easily morph into a protracted real-life nightmare.
While lacking public accountability, the committee is mandated to ferret out such ambiguous phenomena as Russian “media manipulation” and “disinformation.” Along the way, the committee could target an array of activists, political opponents or irksome journalists. In any event, its power to fulfill “such other duties as the president may designate” would be ready-made for abuse.
The committee is to be selected by presidential appointees, including the director of the FBI — an agency with leadership that has all too often pursued covert and overt political agendas, from the times of J. Edgar Hoover to James Comey.
All in all, the provision is a gift for the next president, tied up in a bow by congressional Democrats.

Even without a new HUAC being formed (yet), politicians are already taking pot-shots at easy targets.

Mike Rogers, the former chairman of the House Intelligence Committee, has accused Snowden of working closely with Moscow...
On the vital question of whether Snowden worked with a foreign power when he was taking the documents he would eventually leak, the House investigation is a tease. There is a section titled "Foreign Influence." Yet all but two of its sentences, including supporting footnotes, are redacted.

Nevermind that Snowden isn't in Russia by choice.

Nevertheless, like the last Red Scare, it was only a matter of time before the hysteria escaped the control of it's originators.

Only two days after the alt-right convention in D.C., Turning Point USA launched Professor Watchlist, a website designed to call out college professors who “discriminate against conservative students and advance leftist propaganda in the classroom.”

As Rebecca Schuman wrote for Slate, in other circumstances, these might be two unrelated events, but “as the president-elect’s surrogates cite Japanese internment as a ‘precedent’ for what may come, any ‘watch list’ of any sort is worrying.”

Turning Point’s founder and executive director Charlie Kirk wrote a blog to explain that the purpose of the list was to expose professors who are out of line: “Throughout the next 120 days, Turning Point USA will be running ads to make sure students, faculty, and administrators see that these professors made the Professor Watchlist.” The 22-year-old closes his post with the chilling phrase: “We believe these people need to be exposed.”
Each listing on the site — 200 professors so far — includes a photo. Clearly the website is less about documenting issues and more about public shaming and potentially targeting.

It isn't just Trump supporters copying the tactics of Hillary supporters. Trump is doing it himself.

True to this “leadership” model, the Trump transition team is now circulating a 74-question survey at the federal Department of Energy. Some of the questions are informational and seem designed to figure out how the department functions. Others promote the Trump agenda of privatizing government activities and commercializing federal agencies. But some are frightening and reminiscent of earlier “Red Scares“ when people were purged from government positions because they were critical of policies or where suspected of left-wing views or connections decades in the past.

Who could have possibly foreseen Republicans co-opting the Neo-McCarthyism smear tactics of Hillary supporters?
Oh, right. History, your stage is set for your encore.