The September 24 summit between President Xi Jinping and US President Donald Trump is no ordinary engagement. Their May summit took place in Beijing and largely centred on economic issues. This one will be on Trump’s home turf and is expected to put strategic questions on the table. Will the Korean peninsula and North Korea’s nuclear programme again be pushed to the margins?In Beijing, both sides focused on their immediate national interests, such as trade, semiconductors, rare earths and...