Let’s be clear that the Crimea issue has impacts far beyond the Baltics. Our rivals worldwide watched Putin’s smash-and-grab of Crimea with the Little Green Men of GRU, his military intelligence service, with intense interest. This playbook can now be copied by other countries, particularly if President Trump won’t do anything about it.

Would Trump, as commander-in-chief, simply let China occupy Taiwan, as the People’s Liberation Army has dreamed of for decades? What about all those tiny little islands in the South China Sea that Beijing nakedly covets? These are questions that the Republican nominee now needs to be asked, plainly and directly.

Come to think of it, Iran has designs beyond its borders too. As do several other countries that are not exactly friends of ours. After the catastrophe of 1914-45, when two world wars killed some 75 million people between combat and genocide, the world, led by the United States, established new international norms that sought to minimize the territorial conflicts that caused the horrors of the twentieth century’s blood-drenched first half.

That effort was imperfect and its not-always-efficient diplomatic mechanisms can sometimes seem downright silly. But the post-1945 world order, led by America, has been far more successful than anything before it. Wars really are rarer now, while major conflict seems all but unthinkable, especially among nuclear-armed powers.