Long-threatened tariffs from U.S. President Donald Trump have plunged the country into a trade war abroad — all while on-again, off-again new levies continue to escalate uncertainty.

Trump's tariffs on all steel and aluminum imports are now in effect, and Canada, its neighbor and long-time ally, will be hit the hardest, being the U.S.'s largest foreign supplier.

Here's what the polls say about Donald Trump's presidential approval rating amid rising tariffs and escalating trade wars with Europe and Canada