Not since the Cold War has Red Square hosted such an alarming spectacle. When Russian president Vladimir Putin gathered a crowd of thousands to celebrate his military annexation of Crimea last week, he demonstrated a now-familiar talent for merging stagecraft with statecraft. Flanked by four Jumbotrons and capped by the dubious proclamation “We are together,” Putin’s victory lap after his Crimea success was a calculated display of bravado. Its immediate aim was to lend the illusion of finality to Russia’s brazen land grab. Yet one element of the performance was real — and final — as it brought an undeniable end to President Barack Obama’s vaunted rapprochement with the Kremlin. Some foreign-policy ideas die a quiet death in obscurity. Putin ensured that the White House’s signature Russian “reset” died very publicly, on live television.

This was almost certainly not what the president had expected when he dispatched a “secret letter” to Moscow during his very first weeks in office in 2009. In that note, Obama offered to squelch the Bush administration’s missile-defense plans in Europe in exchange for Russian help on Iran. This was the origin of the reset, and it was the first in a series of misplaced assumptions and false hunches that met an ignominious end last week at the walls of the Kremlin.

The first and most basic error among the White House’s judgments was that history had ended in Europe, or at least that as a geostrategic theater the region would remain quiet. The second misfire was to assume that if troubles did arise, Europe could quell any dustups along its periphery. The third mistake was to prioritize grand bargains with large powers like Russia, even at the cost of neglecting traditional allies like the United Kingdom or vibrant ones like Poland. The fourth and most dangerous misread was that the Kremlin was willing to act as a responsible international partner. Whatever the flaws of Putin’s Russia, the White House clung to the belief that at least it was a country with which the United States could do business.

What is remarkable about the recent Crimea crisis is that it revealed just how many calls the White House got wrong. The eastern edge of Europe is not a dormant strategic fault line but one of the world’s most active. The EU is underprepared for the full-contact geopolitical competition that now predominates beyond its borders. Agreements with Putin are at best dubious propositions. And he is a revisionist leader of the first magnitude. Indeed, Putin’s Crimean adventure is not a simple snatch and grab. It is rather part of a systematic effort to undo the post-1989 settlement of Europe. The consequences for the United States are profound.

Over the course of a single weekend in Crimea, Russia ruptured a framework of historic agreements that have guaranteed peace in Europe for two decades. In the case of Ukraine, these included the Budapest Memorandum (1994), U.N. Document A/49/765 (1994), the NATO-Russia Founding Act (1997), and the Russo-Ukrainian treaty (1997). They affirmed Russia’s pledge to never invade Ukraine’s territory, alter its borders, or challenge its independence through force of arms. Collectively, these promises facilitated Ukraine’s surrender of its nuclear arsenal, NATO’s eventual expansion eastward, and one of the longest stretches of unthreatened tranquility in Europe since the French Revolution.

Worse than a broken promise, Putin’s seizure of Crimea marks the second time in half a decade that Russia has redrawn the map of Europe. The brief but bloody invasion of Georgia in 2008 was the first example of Moscow’s revisionist strategy at work. Ukraine represents a second. The dangerous question that now presents itself to the United States and NATO is: Where and when will there be a third? The attempt to answer this can yield insight into how America should respond to the current crisis and what steps it might take to prevent a future one. Unfortunately, the administration is currently ill prepared for the task.

Surprising as it might seem, the United States lacks even a basic strategy for dealing with Europe’s restive east. As a result, talented U.S. diplomats and servicemen have navigated the Ukraine crisis without a clear idea of what the president’s objectives are, how the United States aims to achieve those goals, what America is willing to sacrifice and what it’s not willing to sacrifice, and what success would look like. What’s more, the lack of an organizing U.S. strategy has impeded the president’s efforts to rally support in Congress for tougher penalties on Russia or to muster a unified policy front among America’s divided allies in Europe. This has sent the worst of all possible messages to Putin: Armed invasions by Russia can be done at low cost and are easily repeatable.

One of the most obvious places where Russia can attempt future revisions to the European security order is in north-central Europe. Echoing Russia’s pretext for the invasions of Georgia and Ukraine, America’s treaty-bound allies in the Baltic region are all former Soviet republics with large Russian minorities. Far from hypothetical, the danger to these countries is perilously real. As recently as last week, Kremlin diplomats began to compare the plight of Russian speakers in this region to that of ethnic proxies in pre-invasion Crimea. It was a chilling warning that raised threat perceptions in the Baltic states and elevated the stakes for crafting the right response to Russian military adventurism. Ideally, such steps would send a resounding message of reassurance to allies, deter future probes of NATO, and position the alliance for a robust defense if conflict broke out. The United States has a variety of means for achieving these aims. Here are four:

Make reassurance a priority. In the past, exposed NATO allies in Europe have wondered if the administration’s “ironclad” pledge to defend them was just talk. Post-Crimea, the White House can significantly assuage these concerns by pre-positioning Marine expeditionary stockpiles from Norway down to Central Europe, formally extending “temporary” fighter detachments to Poland and Lithuania for the foreseeable future, and accelerating plans to build out the physical infrastructure of U.S. missile-defense assets in Central Europe.

Deter unexpected threats to frontline NATO. Let’s put the Pentagon’s “rotational force” concept to the test. One of America’s brigade combat teams is already earmarked for rotational duties in Europe. It should be deployed immediately to an exposed European ally like Poland. Along with similar forms of conventional U.S. deterrence, the positioning of American boots on allied soil would force Russia to recalculate the odds of a successful revisionist foray into NATO’s territory.

Put the “defense” back in collective defense. NATO was established as a collective defense organization, and that is precisely how it should be geared after the International Security Assistance Force mission concludes this year. Making the territorial defense of the alliance the focus of this year’s NATO summit in the U.K. is a great way to start. Practicing NATO’s contingency plans for the defense of frontline allies is another. And the alliance should be up front about the purpose of these exercises: to guarantee the territorial integrity of NATO countries near Russia.

Maintain U.S.-European military cooperation after Afghanistan. One of the biggest concerns of NATO allies is that transatlantic military cooperation will be reduced when the mission in Afghanistan winds down. The United States can work with Europe to find new areas of military cooperation. General Philip M. Breedlove, commander of the U.S. European Command, told Army Times in a recent interview that the United States has canceled 45 percent of military-to-military training events with European militaries. This is unacceptable. In light of recent Russian aggression, the Department of Defense should prioritize U.S. training missions in Central and Eastern Europe over others on the Continent.

By putting these steps in place now, the United States can greatly limit Russia’s range of options for destabilizing the East. This process begins by fixing the administration’s false assumptions from the past, bolstering American credibility amid the present Crimean troubles, and ensuring that territorial stability remains the norm in 21st-century Europe, not the exception.

Of course, that choice is ultimately up to the president. Let’s hope he makes the right one.

 - Luke Coffey is the Margaret Thatcher Fellow at the Heritage Foundation

Editor's Note: Peter B. Doran, direct of research at the Center for European Policy analysis (CEPA) also contributed to this article.