WASHINGTON The IMF and World Bank's semi-annual gathering of finance ministers and central bank governors gets underway in Washington, against the backdrop of new trade threats from the world's two largest economies. Last week, China unveiled new export restrictions on critical minerals, prompting a fierce response from U.S. President Donald Trump, who said he would impose new 100 percent tariffs on Beijing in response. The news, delivered just after U.S. stock markets closed on Friday, sent