During the Cold War American and German military planners were at odds over the positioning of allied forces. The Germans wanted them deployed on the Fulda Gap frontier to destroy the first Warsaw Pact tank that crossed it. At the same time, they rejected a “fallback” strategy that meant Germany would surrender a huge chunk of its territory to cope with the Red Army’s blitzkrieg.

American planners, by contrast, reasoned that the allies could not stop the Warsaw Pact invasion at Germany’s border since the aggressors enjoyed a decisive advantage in men and material. As compensation the defenders would withdraw behind the Rhine River, compelling the Red Army to pause at this water barrier. This would allow NATO units to regain their composure and resist the onslaught from the East with more favorable odds.

But there was another element to this dispute, and it has a bearing on the Western response to Russian aggression in Central Europe today. The Germans wanted Americans to be involved in the conflict from the outset so that the Red Army would never launch the invasion in the first place. They reasoned deterrence rested on the prospect that Americans would die on Day One and thereby guarantee Washington would respond with purpose to the enemy assault. With this knowledge in mind, the Red Army commanders would conclude an invasion of Germany was too risky to justify.

Today, the most vulnerable members of NATO in the East Baltic Sea region share a common border with Russia and desperately want American boots on the ground—not combat engineers constructing an antimissile system in Poland to evaporate Iranian rockets—to deter a reckless Russian military provocation. The prospect that U.S. troops will die should Russian troops cross their borders will give meaning to Washington’s pledge to honor Article Five guarantees. After all, the Americans have demonstrated on numerous occasions that if challenged, they will fight.

Critics might deem this a dangerous and provocative proposal. But if adopted with diplomatic initiatives and sanctions that bite, it is the best way to keep the peace. This is not merely a PR ploy favored by Madison Avenue flakes working to stoke the defense budget for the military-industrial complex, it is grounded in facts on the ground that will gain Putin’s attention.

At present, Putin says that he has no intention of invading eastern Ukraine. The concentration of his combat forces in the area suggests otherwise. His words mean nothing, and given the ambiguity of the Western response—justified by a judicious reluctance to escalate the conflict but also a consequence of pressure from powerful economic interests in Europe and the U.S. that covet Russian business—Putin may conclude that his opponents are too timid, divided and under the influence of their own oligarchs to honor Article Five guarantees. History instructs, however, that ambiguity is dangerous: ambiguity prompted two world wars in the last century, and it threatens the peace today.

That said, Putin has reason to believe that the West will talk the talk but not walk the walk and under the claim that he is protecting vulnerable Russians, in the “near abroad,” he may occupy eastern and southern Ukraine. In addition, his bravado will divide the allies, prove NATO is a hollow shell and fragment an EU already in turmoil.

The problem here is that Putin’s policies conflict with Russia’s capabilities. Anyone, not only professional military strategists, can understand Putin’s delusions by going to their computer and Google in three measures for Russia: population, gross domestic product (GDP) and military expenditures. Then, do the same for the United States, the European Union, Japan and South Korea. Russia has a population of about 148 million, the U.S. over 300 million, the EU approaching 500 million, Japan 128 million and South Korea half that amount. (And let us not forget Australia, Canada and New Zealand.) Get the picture? It is even more dismal for Putin when you turn to GDP and defense spending.

This is not an attempt to demean Russia or its people: Russia is a great nation that has made magnificent contributions to world culture and the Russian people made enormous sacrifices in the twentieth century to destroy European fascism—as did the Ukrainian people.

Disregarding Russia’s comparative weakness, Putin has demonstrated a resolve not found among all the Western democracies, and as a dictator he can engage in reckless behavior that they cannot emulate even though the “correlation of forces” favors them by a wide margin.

Consequently, a growing number of American security analysts favor a deployment of U.S. units to Eastern Europe ASAP to demonstrate that a Russian invasion of Ukraine represents a monumental blunder on Putin’s part—once shots are fired, unpredictable but dangerous outcomes are likely.

Dick Krickus is a Distinguished Professor Emeritus at the University of Mary Washington and had held the H. L. Oppenheimer Chair for Warfighting Strategy at the U.S. Marine Corps University. His forthcoming monograph, Russia after Putin, will be published by the U.S. Army War College.