What If?

Suppose the Russian intelligence service engineered a coup in Canada, overthrew the government, and installed a pro-Russian, anti-U.S. puppet government. Then they shipped in billions of rubles worth of weaponry and threatened to have Canada join a pro-Russian, anti-U.S. military alliance. How would the U.S. react? If the U.S. were threatened as we have threatened Russia, we would react just as Russia is reacting, or worse. Actually we invade countries even when we are not threatened in the slightest.