U.S. President Donald Trump’s former Treasury Secretary Steven Mnuchin said on Wednesday that tariffs on U.S. imports are necessary to rebalance trade more in favor of the world’s largest economy, but cautioned that financial markets need more clarity. “The market really wants certainty and it will adjust to whatever they are,” he said at the Bloomberg Invest conference in New York. “The problem right now is we don’t have certainty.” He said he supports imposing a simpler 10% tariff across the board that would serve as a consumption tax on foreign goods. Trump’s 25% tariffs on imports from Mexico and…