Although the presidential election hasn’t yet been settled, the results so far have clarified at least one thing: The trajectory of U.S. foreign policy is likely to take two starkly divergent paths, neither of which was the conventional wisdom just a few days ago. One would lead to a return to a relatively bipartisan, internationalist U.S. approach to the world. The other is “America First” on steroids.

What’s clear already is that predictions of a landslide victory by the Democrats, including a Democratic takeover of the Senate, were wrong. If Joe Biden ends up winning the presidency, he will most likely face a Republican-led Senate and a weakened Democratic majority in the House. This will require him to seek help from Republican lawmakers with common interests to assemble his administration and advance his agenda. Foreign policy is the best opportunity for a Biden administration to succeed in getting some Republicans on board.

This could mean a quick return to irrelevance for the progressive wing of Biden’s own party, which was betting on Democrats being so powerful that post-election negotiations over policy and personnel would occur between the two sides of their own caucus. Just before the election, progressive foreign policy officials in Congress were publicly airing their plans to bargain for Cabinet positions and agenda items. The vote has changed all of that.

Now, even if Biden does win, he will likely need Republican Senate votes just to confirm his team. Biden officials have consistently said they want to work with centrist Republicans who share their overall national security vision. But will a GOP that finds itself back in opposition want to play along?

“It’s really up to the Republicans,” said Rep. Tom Malinowski (D-N.J.), a former State Department official who just won his first reelection. “There are plenty of Democrats including Joe Biden who want to forge that common ground. So the question is, will the Republicans who actually claim to agree with those principles, who think the McCain-Romney vision for foreign policy is the right one, help Biden where that vision overlaps with his? He is going to need that help.”

Several GOP foreign policy operatives told me that, if Biden is elected and Republicans retain control of the Senate, GOP leaders anticipate having significant leverage, especially regarding senior-level appointments. The idea is not to thwart all potential Biden nominees, but to pressure a Biden administration to avoid far-left progressives and former Obama administration officials the Fox News crowd already dislikes.

Take the position of secretary of state, for one example. The shortlist has included Sen. Chris Murphy (D-Conn.), former national security adviser Susan E. Rice, Sen. Christopher A. Coons (D-Del.) and former deputy secretary of state Antony Blinken.

Progressives favor Murphy, and Rice has been a political target of conservatives since the 2012 Benghazi attacks. Rice threatened to run against Sen. Susan Collins (R-Maine) and raised money for Collins’s opponent — but now Collins has won reelection. Right or wrong, there’s no way that GOP senators would accept Murphy or Rice. Coons and Blinken, considered centrists, are well known and widely accepted among the GOP establishment.

Several GOP senators, including Tom Cotton (Ark.), Marco Rubio (Fla.) and Josh Hawley (Mo.), are eyeing a run for president in 2024, making any cooperation with a Biden administration politically complicated. But the idea that the GOP can follow Trump’s foreign policy and still claim the legacy of Ronald Reagan becomes untenable if Trump loses. And don’t underestimate the willingness of some Republicans to work with Biden for the purpose of pushing back against the populists and isolationists on the left and right, their common enemies.

Some Democratic lawmakers say Biden’s foreign policy was always closer to the traditional GOP approach of alliances, free trade, overt support for American values abroad and robust U.S. engagement on several continents. If Trump somehow manages to squeeze out a reelection victory, they say, it will be a doomsday scenario for internationalists in both parties.

If Trump wins, expect him to purge all GOP officials who restrained his foreign policy instincts during his first term. Trump administration officials confirmed to me that an emboldened White House would likely ask almost all political appointees to resign immediately. Trump would then replace them with hardcore political loyalists, snubbing career Republican professionals who might try to thwart his MAGA agenda. On foreign policy, that could mean drastic withdrawals of U.S. troops from Europe, South Korea, Iraq and Afghanistan and the further dismantling of the national security bureaucracy many GOP leaders have long supported.

“Lindsey Graham is going to find a lot more to like in a Joe Biden presidency than a Trump-John Ratcliffe-Lou Dobbs second term,” Malinowski said, referring to the newly reelected South Carolina Republican senator.

A Biden administration could be the last chance to return to a bipartisan, internationalist foreign policy that moderate Republicans and Democrats have long championed and that has provided 75 years of relative international peace and prosperity. But first, Biden has to win, and some Republicans have to put country over party.

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