Almost all media commentators seem convinced that Donald Trump’s foreign policy in his second term is a disaster. He is bogged down in Iran, snookered in Ukraine, his tariff agenda has failed and he has alienated his NATO allies. But this consensus has been too hastily formed. Looking at the bigger global picture, Trump’s foreign policy has been a spectacular success. Take the western hemisphere. We have the so-called “Donroe Doctrine,” the updated version of the 19th-century Monroe Doctrine. In 1822, president James Monroe, having welcomed South America’s overthrow of Spanish and Portuguese imperial rule, stated that Latin American nations...