It’s disappointing that President Trump’s effort to de-nuclearize North Korea has not been successful, but it shouldn’t be surprising.

After all, if you were Kim Jong Un, you’d be happy to talk about giving up your nuclear weapons, but you wouldn’t be willing to do anything more than talk.

Okay, happily, none of us are Kim Jong Un. Kim may smile a lot, but he’s not a nice guy. He has killed and starved a lot of people, and he oppresses 25 million more. None of us would want such crimes on our conscience, and we also wouldn’t want to live in the condition of fear and paranoia that obviously envelops everyone in North Korea.

Still, Kim controls North Korea, including its nukes, and so we have to deal with him as he is.

In fact, in diplomacy, it’s a continuing challenge to look at the situation from the other guy’s point of view. Why is the other man (or woman) across the bargaining table doing whatever it is he’s doing? Is it because he’s smart? Crazy? Cruel? Dumb? Whatever his motivation, that’s what the effective diplomat has to figure out so as to develop the optimum strategy.

On the other hand, if you don’t wish to bother about what the other guy is thinking, that’s fine, but then there’s no diplomacy—or, maybe, only neglecting or fighting. And if war is hell, war against a country with nuclear weapons is worse.

Yet it is because nuclear countries are such unpleasant antagonists that Kim doesn’t intend to give up his arsenal. He can look around the world, and he can see that he is more secure because of his stash of a-bombs.

And we can see that, too: In addition to North Korea, which exploded its first nuclear device in 2006, there are eight countries in the world that possess nuclear weapons, either officially or unofficially—and all are strong. We can list them in the order in which they built their first one: the U.S., Russia, Britain, France, China, Israel, India, and Pakistan.

So of the 195 countries in the world, the nuclear powers form a kind of exclusive club, even if the club members don’t necessarily like each other very much.

Still, club membership has its benefits. Nobody—not even another club member— wants to mess with a member, for the simple reason that it could hurt.

That’s why, in the wake of the bloody February 14 suicide bombing within Indian territory, blamed on neighboring Pakistan, the two countries are nevertheless being careful. India and Pakistan are playing a little bit of tit for tat, but only a little. As Pakistani leader Imran Khan said on February 27, “With the sort of weapons we both have, can we afford any miscalculation?”

Furthermore, all the other countries in the world—even the rich ones—are notably weaker; that is, they are dependent on nuclear countries for their own defense. We can put Germany in this category, because it relies on the nuclear members of NATO, namely, the U.S., Britain, and France. And as for Japan and South Korea, they depend directly on the U.S. We might pause to observe that while it might be tempting to be a free rider, it’s still a bit humiliating—and in any case, the fun only lasts so long as the free ride lasts.

Moreover, if we look at the countries that once possessed nukes, but no longer have them, we see a bitter lesson—and that’s a lesson that you can bet Kim Jong Un has absorbed.

The three ex-nuclear countries are Belarus, Kazakhstan, and Ukraine, which were left with “legacy” nukes on their soil when the Soviet Union collapsed in 1991. Over the next few years, all three nations, urged on by international arms-controllers, surrendered their weapons.

To be sure, it was a nice gesture, but what’s been the fate of those countries? Well, Belarus is an overt Russian satellite, and so, more or less, is Kazakhstan. And while Ukraine is avowedly and keenly independent, it has been victimized by the Russians. In fact, Russia conquered one of its provinces, Crimea, in 2014, and ever since, Russian troops have been nibbling on Ukraine’s frontier; total estimates of Ukrainian casualties run to about 10,000.

So as we think about these three beleaguered countries, we might think of that famous f-bomb line from the 1978 movie Animal House, in which one of the characters learned a bitter lesson about the limits of trustingness.

Moving right along, as we continue to look at the world through Kim Jong Un’s eyes, we might think of another category of non-nuke countries: those that came at least somewhat close to having nuclear weapons, but for whatever reason, did not hit critical mass.

These states include, most notoriously, Iraq and Libya—you know, the countries once led by dictators Saddam Hussein and Muammar Gaddafi. Those two autocrats are now both deceased, of course, and neither died happily; Saddam was hanged in a Baghdad prison, and Gaddafi was lynched out in the desert. Once again, it helps to be strong, and this is doubly true if you’re a dictatorial tyrant who must rule by force. In such cases, strength is everything.

Indeed, it’s entirely possible that if Saddam and Gaddafi had managed to get themselves into the nuclear club, they could have staved off regime-change—and could even be enjoying life today as feared and powerful dictators.

Once again, Kim Jong Un knows all this. That’s why he’s happy to talk, and talk some more—but nothing more. He enjoys being in the nuclear club, not in the Saddam/Gaddafi club.

Oh, and one more thing: If you lived in Northeast Asia, with tough customers such as China and Russia right there on your northern border—and with rival South Korea on your southern border, and with historic enemy Japan just across the water—you’d be thinking hard, always, about national defense. Why, you’d likely be thinking to yourself, Nukes are a guy’s best friend.

So where does all this leave President Trump and the U.S.? If no country in its right mind will give up its nuclear weapons, then what are the prospects for arms control? For peace?

Here’s the realistic bottom line: If you want peace, prepare for war, including, most urgently, missile defense. We should have been preparing our missile defenses, like, yesterday.