Mexico and Canada have managed to avoid U.S. tariffs — for now — after their leaders came to last-minute agreements with President Trump. But barring another eleventh-hour deal, tariffs on goods from China were scheduled to go into force Tuesday, raising the specter of a trade war that could rile the global economy and punish American consumers.

The Canadian prime minister said the country has a $1.3 billion border plan and 10,000 "frontline personnel" protecting the border.