Donald Trump will close out this week's Conservative Political Action Conference (CPAC) in National Harbor, Maryland on Saturday, but this year he won't be the man of the hour. The conference, which kicked off Wednesday, will certainly have plenty to say about Trump and his first term in office, yet Trump won't be the indispensable figure for the thousands of conservative activists in attendance. After 47 years of organizing, CPAC finally has the fight for which it has built itself.

And it has Bernie Sanders to thank for it.

Sanders won't appear at CPAC, of course, but his presence will be felt in nearly every presentation and in every corner of discussion. Sanders' socialist branding — small-S or otherwise — has given CPAC the explicit and immediate framing it has long used as one of its key themes. In this election year, Sanders' rise in the Democratic presidential race has reinvigorated the fight against socialism that marked the Cold War years of conservatism.

Trump will use his own appearance to assume the mantle of leadership in this fight, and has indeed already positioned himself as the best banner-carrier in this battle. He began that effort in his State of the Union address with a clever decision to invite Juan Guaidó as his guest, highlighting Guaidó's fight to remove Venezuela's socialist strongman Nicolas Maduro from office.

"The United States is leading a 59-nation diplomatic coalition against the socialist dictator of Venezuela, Nicolas Maduro," Trump said in introducing Guaidó, telling him directly to let Venezuelans know that "all Americans are united with the Venezuelan people in their righteous struggle for freedom." Turning back to Congress, Trump declared, "Socialism destroys nations, but always remember: freedom unifies the soul."

If that was a dare on Trump's part to Democrats, their voters appear to have called him on it. Sanders has only gained momentum since Trump's February 4 speech, essentially tying Pete Buttigieg in the Iowa caucuses and then winning contests in New Hampshire and Nevada more convincingly. With Sanders rising in the polls for Saturday's South Carolina primary and in the pole position for many of the Super Tuesday races, the big question at the moment seems to be not whether Sanders can win more delegates, but whether he can win enough to ensure a first-ballot nomination at the Democratic National Convention in Milwaukee.

The prospect of having a socialist at the top of the Democratic ticket in November has simplified matters for CPAC and for conservatives more generally. Even with Trump's surprise win in 2016, tensions remained within the conservative coalition about his performance as president. CPAC has tried to unify the Right in the past few years by focusing on the us-vs-them aspect of the Trump era, but significant voices in the coalition have continued to raise concerns about Trump's comportment as well as some of his policies. Those efforts to enforce unity have continued this year with a very public disinvitation to Sen. Mitt Romney (R-Utah) after his vote to convict Trump in his impeachment trial, becoming the only senator in U.S. history to vote to remove a president of his own party.

The more Sanders wins, though, the less those divisions matter. That may well be true in the Democratic primary as well, where Sanders has come under attack for his praise not just of the "Scandinavian" socialism he professes to represent but also of overtly repressive leftist regimes like the Sandinistas, Fidel Castro, and communist China.

Democrats have begun to expose their own divisions by speaking out against Sanders, and not just Sanders' presidential competitors. Sanders' Senate colleague Robert Menendez (D-N.J.), an American of Cuban descent, told reporters, "I don't understand how you can praise any of that. ... I certainly think it's wrong for the person who would be the leader of the free world."

The activists at CPAC will certainly agree with Menendez on that issue. Trump's qualifications for that job may have been part of the discussion at CPAC under different circumstances, but no longer. Even the MAGA agenda will take second place to the existential necessity of stopping a socialist from winning the White House.

CPAC's agenda already reflects this reinvigorated focus. Eight of the presentations at the conference are specifically dedicated to socialism, such as Thursday morning's session on "Socialism: Wrecker of Nations and Destroyer of Societies," emceed by former Trump administration national-security official KT McFarland. Half of those events are main-stage sessions as opposed to breakout sessions, showing the heightened focus on this mission.

By contrast, only three general-session events other than Trump's Saturday address to the conference has Trump as its explicit focus. Two of those are main-stage discussions with Trump family members (Lara Trump, Ivanka Trump), and the other an address by Trump campaign booster (and Donald Trump Jr. girlfriend) Kimberly Guilfoyle.

To be sure, the conference will have plenty of training sessions for organizers and discussions of other policy areas. The most prominent theme, however, will be the call to arms against socialism. Attendees will have the opportunity to learn about "Exposing and Defeating the Socialist Plot to Hijack America" in one session, or to hear "the Unshackled Voices of Socialist Regimes." Some will learn "words that work in persuading others [against] socialism" in one breakout session, or find out how to beat "Socialism & The Great Awokening" from the main stage.

The agenda has its own message to activists — emphasize "socialism." The words "liberal" and "progressive" are entirely absent from this agenda. In any other cycle, that would be seen as either hyperbole or an anachronism. Sanders' rise in the Democratic primary has made it both timely and at least within reach of Sanders' own rhetoric, especially after his remarks about Castro and the communist regime in China this week.

Make no mistake about it — Sanders will be the indispensable man at CPAC. And he might just end up as its most unifying figure since Ronald Reagan.

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