Way too early, of course, but I'm guessing it's going to be Kamala Harris.

[honest.abe]

24. From wikipedia..

Foreign policy

In April 2017, responding to the Khan Shaykhun chemical attack, Harris charged Syrian president Bashar al-Assad with attacking Syrian children, and stated "the clear fact that president Assad is not only a ruthless dictator brutalizing his own people -- he is a war criminal the international community cannot ignore." She called on president Trump to work with Congress on his administration's "lack of clear objectives in Syria and articulate a detailed strategy and path forward in partnership with our allies."[188]

Harris speaks with Palestinian students at the Al-Quds University in the State of Palestine, West Bank, November 12, 2017
In 2017, Harris gave a public address to AIPAC attendees. She said: "I believe Israel should never be a partisan issue, and as long as I’m a United States senator, I will do everything in my power to ensure broad and bipartisan support for Israel’s security and right to self-defense."[189] She has opposed the Boycott, Divestment and Sanctions movement targeting Israel.[190] Harris was a co-sponsor of a Senate resolution expressing objection to the UN Security Council Resolution 2334, which condemned Israeli settlement building in the occupied Palestinian territories as a violation of international law.[191][192][190] At the AIPAC conference, Harris said that "the first resolution I co-sponsored as a United States senator was to combat anti-Israel bias at the United Nations".[191] She also supported Senate resolution celebrating the 50th anniversary of the reunification of Jerusalem.[193][194] In late 2017, Harris traveled to Israel, where she met with Israeli Prime Minister Benjamin Netanyahu.[191]

In October 2017, Harris condemned the genocide of the Rohingya Muslim minority in Myanmar and called for a stronger response to the crisis.[195]

In February 2018, Harris was one of 18 Democratic senators to sign a letter to Trump stating that he lacked the authority to launch a preemptive strike against North Korea without authorization from Congress. The letter stated: "Without congressional authority, a preventative or preemptive U.S. military strike would lack either a constitutional basis or legal authority."[196]

In 2018, after Trump announced the United States was withdrawing from the Joint Comprehensive Plan of Action, Harris released a statement saying the decision "jeopardizes our national security and isolates us from our closest allies" while calling the Joint Comprehensive Plan of Action "the best existing tool we have to prevent Iran from developing nuclear weapons and avoid a disastrous military conflict in the Middle East."[197] In late 2018, she voted to withdraw U.S. military aid for Saudi Arabia's war in Yemen. Harris also backed a resolution blaming Saudi Crown Prince Mohammad bin Salman for the murder of dissident journalist Jamal Khashoggi in the Saudi Arabian consulate in Istanbul.[198]

Harris supported the Iran nuclear deal to prevent Iran from acquiring weapons of mass destruction.[190] In December 2018, after Secretary of State Mike Pompeo announced the Trump administration was suspending its obligations in the Intermediate-Range Nuclear Forces Treaty in 60 days in the event that Russia continued to violate the treaty, Harris was one of 26 senators to sign a letter expressing concern over the administration "now abandoning generations of bipartisan U.S. leadership around the paired goals of reducing the global role and number of nuclear weapons and ensuring strategic stability with America's nuclear-armed adversaries" and calling on Trump to continue arms negotiations.[199]

Harris voted in favor of a $675 billion defense budget bill for the 2019.[200] Harris said that North Korea is "one of the most serious security threats".[201] In February 2019, after former Acting FBI Director Andrew McCabe claimed that President Trump believed the claims of President of Russia Vladimir Putin over U.S. intelligence agencies' reports on the subject of North Korea’s missile capabilities, Harris told reporters, "The idea that the president of the U.S. would take the word of the head of Russia over the intel community is the height of irresponsibility and shameful."[202]

https://en.wikipedia.org/wiki/Kamala_Harris#Foreign_policy