The North Atlantic Treaty Organization was born in response to Soviet expansionism in Europe following World War II. Moscow’s designs on Western Europe were clear. And so began the U.S. policy of containment of the Soviet Union, the most important element of which was the U.S. pledge to defend Western Europe against Soviet attack. That pledge was codified in the Washington Treaty establishing NATO in 1949. The treaty’s Article 5 declares that “an armed attack against one or more” of its members “shall be considered an attack against them all.”

The Soviet Union is no more, but the alliance has hardly grown moribund. In the 1990s, NATO went to war twice in Europe to stop atrocities in the disintegrating former Yugoslavia and deployed peacekeepers there in the aftermath. NATO invoked Article 5 following the 9/11 attack on the United States and took command of the military mission in Afghanistan from 2003 until 2014. In 2011, NATO conducted air strikes on Muammar Qaddafi’s Libya to prevent the slaughter of opponents of the regime, which then collapsed. NATO is currently involved in myriad assistance and training programs with partner countries. In the wake of Russia’s 2014 annexation of Crimea and invasion of Eastern Ukraine, President Obama flew to Estonia, to offer reassurance to the presidents of three Baltic countries—once captive Socialist Republics of Moscow, since 2004 members of NATO—that the United States remains committed to their defense under Article 5.

For his part, Donald Trump has called NATO “obsolete,” citing its Cold War origins and a primary security threat that now comes from radical Islam. He has said NATO costs the United States “billions” and that allies don’t contribute a fair share—a point he has also made about our Asian alliance relationships. Two generations ago, when we were a rich country, it might have made sense for the United States to subsidize the security of others countries, he has said, but not now that America is poor. He also seems to question the value of what the United States is committed to defend: After the recent terrorist attack there, he remarked that Brussels has become a “hellhole.” Trump has also expressed admiration for Russian President Vladimir Putin, and while he seems to find Russia’s military intervention in Ukraine regrettable, what seems to irk him still more is that the United States rather than our European allies, in his view, has shouldered the lion’s share of the burden of responding to it.

Each of his substantive points is readily rebuttable. First, the United States is still a rich country—the largest economy in the world and fifth in GDP per capita, according to the International Monetary Fund. Second, the United States reaps great benefits from NATO and its other alliance relationships. Trump points to the so-called free-rider problem, according to which European governments can spend as they wish on domestic programs because they need not pay for their own defense. But it is far from obvious that the United States could more cheaply protect its national interests without these alliances. We have fought bloody wars to prevent the domination of Europe and Asia by powers hostile to our political principles, and the deterrence value of our alliances and our ongoing military presence in these areas is a bedrock element of keeping the peace.

Third, the external threat radical Islam poses to the United States and its allies is now manifesting a homegrown counterpart in Europe, but Europe’s capitals have hardly become “hellholes.” And in coping with these new threats, an approach in which the United States remains a willing partner stands a better chance of success than one in which we act as if oceans provide the same protection they did 150 years ago.

Fourth, as for Russia, Trump’s affinity for Putin is perhaps a sign of respect for power effectively wielded, something Trump believes the United States has been failing to do. But complaining bitterly about the cost of deterring Putin is hardly the way to deter him from further adventurism.

Though Trump seems to ad-lib his way through questions about policy matters, his view of NATO and other alliances is not incoherent. I doubt he simply fails to understand that NATO has been the cornerstone of the security relationship between the United States and Europe for nearly three generations. Probably he did not miss the fact that after the Soviet Union broke up, NATO found a new “out of area” mission countering radical Islam in Afghanistan. More broadly, nor did he miss the fact that the alliance has more recently renewed its focus on deterrence and territorial defense in light of Russia’s rekindled adventurism. He likely understands that the challenge of the Islamic State as a coordinator of attacks in Europe suggests that NATO’s engagement in counterterrorism missions will continue. It may even have come to his attention that along with the global U.S. commitment to keep sea lines of communication open, NATO is the baseline test of the credibility of all U.S. security commitments, such as those to Japan and South Korea—and therefore of the U.S. commitment to maintain the global order that previous presidents worked so hard to set up and manage.

The Donald Trump problem isn’t ignorance. It’s that he believes we can safely jettison our commitments until we get a “better deal.”

According to textbooks on how to negotiate, lest you overpay, you must enter a negotiation knowing your BATNA—“Best Alternative to a Negotiated Agreement.” Trump’s BATNA is a world on its own, without U.S. engagement. Rather than being willing to pay a price to avoid living in such a world, he believes the world should be paying us for the services we render. If it doesn’t, best of luck—and to us as well.