WASHINGTON — President Trump’s self-described “great relationship” with his Chinese counterpart, Xi Jinping, will be put to the test starting later Tuesday as the US president travels to Beijing for the first time in nine years. Over two days of meetings, Trump is expected to raise a series of concerns about artificial intelligence, the global economy, trade and nuclear weapons. He will also be traveling with a who’s who of CEOs to help him make his case for Chinese investment in America. Xi, in turn, wants to see America tone down its support for Taiwan — the self-governing island China...