THE ABCs of summits is that the leaders who go to them know beforehand what the end-game is. After the meet and greet and photo-ops, they know what will be signed on the dotted line and what will be written in the subsequent communique. They never engage in such meetings without prior meticulous preparations conducted by their aides. This holds doubly true if the leaders are not allies but adversaries.

The extraordinary breaking news that US President Donald Trump has accepted North Korean leader Kim Jong-un’s unprecedented offer to sit down for talks deserves the screaming headlines: “Political Gamble of the 21st Century, Extraordinary Overture, Miracle, Mind-Boggling Summit, Unmatched Moment of History”. These two leaders were, after all, ready to blow their countries up to smithereens, killing possibly millions of people along the way.

But when they meet in May at an as yet undetermined venue, what kind of deal is Kim truly willing to offer and what kind of deal is Trump truly willing to accept? The South Korean officials who passed on to Trump Kim’s invitation letter said he was “committed to denuclearization”, had pledged that North Korea will refrain from any further nuclear or missile tests and understands that US-South Korean military drills must continue.

However, the North has halted missile and nuclear tests during previous talks, only to resume them when it failed to get what it demanded. And North Korea has not yet promised to abandon its nuclear weapons completely. All Trump really got for his agreement to meet Kim was a vague denuclearization statement and an agreement to refrain from future missile and nuclear testing with no guarantees. Trump’s move recalled his declaring Jerusalem as Israel’s capital and pledging to move the US embassy to Jerusalem without securing anything in return from Israel.

On North Korea at least Trump has laid out a clear precondition for talks: give up its nuclear weapons. But nothing in North Korea’s rhetoric or history suggests that it would be willing to abandon its nuclear program altogether without getting some major concessions from the US, including accepting the legitimacy of the Kim government and agreeing to remove US troops from South Korea. It’s far more likely that the North would simply agree to a temporary freeze.

Trump has some leverage over Kim. It is likely that Kim asked for this summit because the most stringent sanctions ever imposed on the North Koreans through the UN Security Council as a result of a US initiative are beginning to impose severe pressure on his regime. Trump says Kim’s interest in negotiations showed US sanctions were working and stressed that they would remain in place until North Korea agreed to a deal. So, Pyongyang might be willing to agree to stop building and testing missiles and bombs in exchange for sanctions relief.

It should be noted that the last major negotiating effort — the six-party talks — collapsed in 2008 largely because North Korea refused to allow inspectors to verify that it had shut down its nuclear program. Rogue countries like Iran have historically given watchdog bodies like the International Atomic Energy Agency the runaround when it comes to verification and monitoring. North Korea will probably not be an exception if it is demanded of them to place its N-program in clear view.

None of the leaders of the US and North Korea have ever met and every US president since Bill Clinton has demanded that North Korea give up its nuclear weapons, to no avail. Trump would relish the chance to pull off an achievement none of his predecessors managed.

Despite all the reservations, any direct US negotiations with North Korea are far better than the alternatives, which include the prospect of a cataclysmic war that would kill millions. If it succeeds in significantly lowering tensions, the summit is worth it.