Donald Trump erects a protectionist barrier around America

US presidents from Ronald Reagan to Bill Clinton and George W Bush have used the White House Rose Garden to celebrate significant moments in America’s drive to liberalise the global economy. 

But on Wednesday, Donald Trump chose the venue to announce steep new tariffs on all imports with extra penalties for many of America’s top trading partners, erecting a protectionist barrier around the world’s largest economy in a watershed shift for US international economic policy. 

“It’s our…