After last night’s shocking news that Donald Trump has accepted Kim Jong Un’s reported invitation to negotiate one-on-one, the question is: What will Trump say if Kim offers him this deal or something even better—the dismantling of its ICBMs in exchange for the full withdrawal of U.S. troops from South Korea?

There are at least three reasons to believe he might be open to such a proposal.

The first is that Trump cares about the direct threat to the American homeland more than anything else. President Obama warned him of the North Korean ICBM threat immediately after the election and he has taken it to heart. He has pursued a unilateral policy and has held open the possibility of a preventive strike without prior approval from Seoul. This is the essence of “America First”—narrow U.S. interests supersede all other concerns. It is a significant conceptual break with traditional American policy since the late 1940s, where the United States treated threats to the homeland and to the allies equally.

The second is that Trump has always had concerns about alliances in general and the U.S.-South Korea one in particular. Since the mid 1980s, he has argued that America’s alliances are a bad deal. Initially his wrath was focused on Japan and the Arab states but in 2013, he said, “How long will we go on defending South Korea from North Korea without payment? … When will they start to pay us?” In an interview with NBC in 2015, he said, “We have 28,000 soldiers on the line in South Korea between the madman and them. We get practically nothing compared to the cost of this.” Perhaps Trump may think that an end to the ICBM program and the withdrawal of U.S. troops from South Korea is a win-win.

The third is Trump’s ego. He sees himself as the world’s greatest dealmaker. He wants to sit down man-to-man with his rival. He cares nothing about America’s historical obligations and is likely singularly motivated by the ICBM threat. In odd ways, he respects Kim. In January 2016 he said of Kim:

You gotta give him credit. How many young guys—he was like 26 or 25 when his father died—take over these tough generals, and all of a sudden ... he goes in, he takes over, and he’s the boss. It's incredible. He wiped out the uncle, he wiped out this one, that one. I mean this guy doesn't play games. And we can't play games with him.

As Victor Cha has written in The New York Times today, there are only two possible negotiating approaches—economic concessions in exchange for a freeze of the nuclear program, as U.S. presidents have done in the past, or going big with a peace treaty that could include the withdrawal of troops. Trump is unlikely to want to repeat the actions of his predecessors. The Bannon deal would allow him to say he eliminated the missile threat and has saved the United States billions of dollars in the process.