President Donald Trump’s trade war, aggressive immigration enforcement and talk of making their country the 51st state has offended many Canadians. While concerns are acute in New England, tourism hubs from Hawaii to New York are reeling from a decrease in Canadian visitors. To quell tensions, Maine leaders erected signs in French to welcome Canadian visitors and New Hampshire’s governor just returned from a Canadian trip she took to strengthen trade and tourism. But hospitality businesses this summer reported a sharp decline in visitors from the North — Canadian travel to New Hampshire is down about 30% this year, according to state officials. But even as families line up, employee Polly Howe said she hadn’t seen many Canadians this summer.