Donald Trump makes a toast as he attends a state banquet with China's President Xi Jinping at the Great Hall of the People in Beijing. AFP via Getty Images It looks like President Donald Trump’s China visit will wind up as positively as anyone could reasonably hope. His host, Xi Jinping, offered at least lip service support for Washington’s central goals in Iran : permanent free passage of the Strait of Hormuz and a never-nuclear Islamic Republic. As important, Beijing gave the president a warm welcome, delivering all due honors to Trump, excellent food and even a “YMCA” serenade. Notably, Xi’s talk of “the Thucydides trap” could signal a sincere desire to avoid serious enmity. (The “trap” refers to 4th century BC Greece, when conflict between dominant power Sparta and rising power Athens led to decades of warring that left both powers reduced; a US-China war now, of course, risks world annihilation.) Another good sign: Xi accepted Trump’s invitation for a return visit to Washington , likely in September.…