Sen. Bob Menendez (D-N.J.) spent years as the top Democrat on the powerful Foreign Relations Committee in the Senate, wielding tremendous influence over Congress, the White House and government agencies. With Menendez facing the biggest crisis of his career federal corruption charges and calls for his resignation from a growing number of his fellow Democrats he is almost certain to lose that position for good.

The upshot would be dramatic, involving big changes to the Democratic Partys approach to international relations and to Washingtons national security establishment.

The foreign policy implications are extremely significant, one Democratic congressional aide told HuffPost. Referring to the West Virginia Democratic senator notorious for challenging his own party, the aide added: You cant overstate the extent to which Bob Menendez was the Joe Manchin of foreign policy.

Menendez holds hawkish views on many global questions, notably Middle East matters such as diplomacy with Iran and the Israeli-Palestinian conflict, as well as Latin American dilemmas like how the U.S. should deal with unfriendly governments in Cuba and Venezuela. Through public advocacy and private pressure, he has pushed for U.S. policy to reflect those opinions even when such shifts clash with most Democrats preferences and risk conflict or human rights violations.

Though Menendez largely supported Presidents Barack Obama and Joe Biden on domestic issues, he broke with both of them on foreign policy in high-profile ways.

For him to be the one who determines the caucus foreign policy agenda is pretty bizarre, said Matt Duss, who served as the foreign policy advisor to Sen. Bernie Sanders (I-Vt.) from 2017 to 2022.

When you know that the chairman of the Foreign Relations Committee has these very hard-line views, that constrains your concept of the possible especially when you have an administration that doesnt want to spend a whole lot of time arguing about foreign policy, continued Duss, who is now the executive vice president of the Center for International Policy think tank.

Menendez temporarily stepped down from his role as the committees chairman last week due to the criminal charges against him , which allege he took bribes in exchange for official favors that benefited Egypt and New Jersey businessmen. He maintains his innocence and his ultimate fate in the Senate remains unclear.

Nearly all Democratic lawmakers broadly share a vision for the U.S.s role in the world: being engaged and powerful but not overbearing, championing democratic principles and encouraging other nations to do the same, and bolstering Americas network of alliances and global coalitions to address concerns like climate change. If Menendez is permanently replaced as the committees chair, his successor could be more focused on promoting that agenda and mend intra-Democratic rifts on international matters.

He was, under both Obama and Biden, in the way of a ton of Democratic Party priorities, the Democratic congressional aide said. No matter who replaces him, the door opens for a much saner policy towards Cuba, Venezuela, Iran and down the line to Taiwan.

A Tense Tenure

On the coattails of Bidens 2020 election victory, Democrats captured the Senate for the first time since 2014, and Menendez rose from ranking member of the Foreign Relations Committee to its chairman.

He quickly signaled that he would not help Biden achieve one of the presidents chief foreign policy promises from the campaign trail: reentering the international pact to limit Irans nuclear program. When Obama helped craft the deal in 2015, Menendez was one of only four Democratic senators to vote against it .