The Europeans got the message.

American presidents since Kennedy have wanted Europe to shoulder more of the burden of its own security. But not until President Donald Trump has a U.S. leader succeeded in getting Europeans to want the same. Of course, the eruptions of a revanchist Russia have helped.

The latest example of Europe’s new groove: The prime minister of Poland, Donald Tusk, announced on Friday plans for all Polish men to undergo military training. Tusk said he wants to increase the size of the army from 200,000 soldiers to half a million, and that Ukraine’s army has 800,000 while Russia’s has 1.3 million. It’s no coincidence that the target set by Tusk would make up the difference.

One far-sighted philosopher prophesied long ago that Russia’s rise would lead to Europe’s revitalization. In 1886, Friedrich Nietzsche wrote that Europe might only shake its feebleness, divisions, and liberal illusions in the face of a growing Russian threat: 

I mean such an increase in the threatening attitude of Russia, that Europe would have to make up its mind to become equally threatening—namely, to acquire one will, by means of a new caste to rule over the Continent, a persistent, dreadful will of its own, that can set its aims thousands of years ahead; so that the long spun-out comedy of its petty-stateism, and its dynastic as well as its democratic many-willed-ness, might finally be brought to a close. The time for petty politics is past; the next century will bring the struggle for the dominion of the world—the compulsion to great politics.