Foreign policy crises are inevitable, and no American president can prevent them from arising. But it is possible to provoke, mismanage, and even exacerbate them, making a fraught situation catastrophically worse. We are only here today in part because John F. Kennedy overruled the hotheads among his advisors—they were in the majority—during the Cuban Missile Crisis. In the anxious heat of an inherently uncertain moment, sober judgment, command of the relevant information, and self-awareness regarding the consequences of one’s actions are crucial.

By all indications Donald Trump lacks these qualities—and as a result, the world is about to become a much more dangerous place. Five potential crises now loom especially large, pertaining to political instability in Europe, East Asia, and the Middle East, the fragility of the international economy, and the consequences of the next major terrorist attack.

Putin might not resist the temptation to hasten the collapse of NATO.

1. For seven decades NATO has served as one of the pillars of the stable and prosperous international order that was constructed on the smoking ruins of the world wars. That order is in jeopardy. Russia used to fear NATO expansion—only in his wildest dreams did Vladimir Putin imagine the utter collapse of the American-led alliance. But enter Trump—who has a more-than-curious soft spot for the brutal Russian authoritarian, and who appears to share that dictator’s disdain for decadent, liberal, democratic Europe—and suddenly some dreams might come true, with potentially wrenching consequences for Europe and for American international political influence. As a new cohort of diplomats and decision makers assess U.S. relations with Europe, Russia would be wise to engage in what physicians call “watchful waiting” to see whether NATO ultimately collapses under the strains of its own political weight. But Putin might not be able to resist the temptation to give history a nudge or capitalize on a sudden flashpoint. A crisis in the Baltics could become very dangerous very suddenly.

2. In East Asia the international politics are subtler, but the prospects for geopolitical transformation and upheaval in the region are at least as likely. The challenge the United States faces is how to adapt to the emergence of a great power while defending core interests and supporting friends and allies. Yet Trump likes to boast of his unpredictability. That may be exactly what you are looking for in a football coach, but it is an awful attribute of a vital military-political ally. Countries in the region, weighing their own local and pressing relations with an increasingly powerful regional giant, will want to know where America stands and have confidence in the clarity of its commitments. Like Russia, China would be best served by keeping its powder dry and watching the Unites States engage in acts of geopolitical self-immolation. But Trump seems eager to pick a fight—or at least a confrontation—with the People’s Republic, and rising powers are usually quick to take offense.

The consequences of a bitter, internecine trade war should not be underestimated.

3. In the Middle East, the administration would appear on the brink of breaking with the long-standing, bedrock, bipartisan U.S. commitment to a two-state solution to the Israeli-Palestinian conflict. Writing a blank check for the increasingly popular, once extremist Israeli hard-right vision of one-state domination will surely lead to even greater political despair among the Palestinian dispossessed and will not advance American interests (or long-term Israeli interests, for that matter). And the extraordinary complexity of the Syrian Civil War would test the diplomatic genius even of a Bismarck. There are no easy answers here, but you can be certain that no policy that starts with the phrase “bomb the hell” will do anything but make matters even worse. And in the Gulf, new American unpredictability, apparent nonchalance about nuclear proliferation, energy independence, and possible confrontations with Iran might send the Saudis, among others, scrambling to build their own nuclear deterrent—a most unwelcome and hazardous development, to say the least.

4. The first big crisis out of the gate, however, will probably be something that sounds much less apocalyptic, but the consequences of which ought not to be underestimated: a bitter, internecine trade war. Even though Trump’s political preferences on most issues have been far from consistent over the years, since the Reagan era he has taken a jaundiced and even antagonistic view of international trade, and a (rather plainly simplistic) promise to reverse bad trade deals was a signature theme of his presidential campaign. With the executive power of the presidency he could easily take actions that would set off a trade war. Such measures will prove an especially harsh lesson in the iron law that actions have consequences. Getting tough with trade partners will not end the game—it is naïve to think they might not retaliate, in part to avoid setting the precedent of crumbling under American pressure. Here it is important to remember that the United States has the second largest exporting economy in the world, with millions of jobs dependent on those thriving businesses. Mexico is our second largest export market, China our third. Moreover, the economics of protectionism are complex and in many ways self-undermining. Setting aside the risk of more expensive consumer goods (which will be felt most acutely by families on tight budgets), American firms that use imported goods as elements of their own production processes will become less competitive due to rising costs. At the same time, suppressing the exports of other countries by blunting their access to the massive American market will drive down the value of their currencies, giving those counties’ products a competitive edge on world markets. (In the 1930s American protectionism helped reduce imports by about 75 percent, but exports plunged even faster, dropping off by almost 80 percent.) Not only is protectionism playing with fire; it will likely backfire.

Perhaps the greatest geopolitical threat posed by the Trump administration is the damage that will be done to America’s character.

5. Finally, it is important to remember that foreign policy begins at home. The disposition of the United States and expectations about its future behavior will shape the geopolitical choices that other countries make in the coming years. Perhaps the greatest geopolitical threat posed by the Trump administration is the damage that will be done to America’s character after the next major terrorist attack, in the wake of which the president-elect will feel tremendous pressure (and is likely predisposed) to take decisive and dramatic actions— possibly including the disproportionate and indiscriminate application of violence abroad, the normalization of torture, and the turning of authoritarian screws at home (through emergency actions that encroach on privacy, due process, and free speech). Such measures would not only not make us safer; they would change who we are, how we understand ourselves, and how we are understood abroad—setting in motion among other nations a grand reassessment of the value of sharing America’s geopolitical objectives.

In sum, as Team Trump takes command of American foreign policy, the geopolitical consequences look grim. Trump’s career and conduct as candidate, nominee, and now president-elect give ample reason to be deeply skeptical that he has the qualities necessary to direct the foreign policy of a superpower. This is no small matter. It is a cliché to say that the world is a dangerous place, but most Americans—with a complacency inured by a lifetime of unprecedented, almost preternatural national security (even as they are subjected to a wall of hysteria from attention-seeking media outlets)—do not fully appreciate the implications of this truism. Foreign policy recklessness can bring ruin.