What will be going on inside the heads of Kim Jong-un and Donald Trump at the Hanoi summit?

Nine months after they first met in Singapore, Kim Jong-un and Donald Trump, the US president, have come together again this week for a high-stakes summit.

They hope to overcome an impasse on how to deal with North Korea’s nuclear weapons programme. But what is really driving the two leaders to a level of rapprochement unthinkable just two years ago?

Trump staking political capital on a win

Donald Trump’s trip to Vietnam reflects a growing reality in the last two years of his first term that foreign policy, not domestic legislation, offers him the best chance of ‘wins’ he can sell at the 2020 election. 

The US president delivered on a string of campaign promises at home in his first two years…