North Korea’s latest provocation—a successful test of an intercontinental-range ballistic missile (ICBM)—brings the long-building crisis on the Korean peninsula to a dangerous flashpoint. For one thing, it’s clear evidence that North Korea aspires not merely to have a nuclear-weapons program, but to be able to target the continental US. And that’s a dangerous aspiration for a risk-tolerant pariah state to have. While some are undoubtedly hoping that the bilateral relationship will evolve into one of long-term deterrence, it’s far from clear that Washington can tolerate a relationship of mutual vulnerability with such an actor.

But we’ve reached a point where only seriously costly options could offer a real prospect of reversing North Korea’s nuclear and missile programs, because those options involve either regime change or war (and perhaps both). True, there’s increased discussion about increased discussion: something I’d feel happier about if the record of previous negotiations were a little less underwhelming. China’s gone back to pushing its idea of ‘a cap for a cap’: a freeze on North Korea’s programs in exchange for a freeze on US – South Korean military exercises. To be frank, that idea’s unappealing. While there’s some residual value in ‘freezing’ programs that have already demonstrated a considerable measure of success, staying in a freeze isn’t a long-term option—and Pyongyang has stated bluntly that it has no intention of denuclearising. (Indeed, it has written its nuclear status into its Constitution.) Not to mention that US – South Korean exercises are a necessary part of ensuring the effectiveness of the alliance.

Sanctions could surely be tightened. But they are so blunt, slow and uneven that it would take years to ensure they exercised decisive leverage upon Pyongyang’s policy choices. Certainly the North Korean economy’s in relatively good shape today ^[1]—comparatively speaking, of course. It’s absolutely no match for the South Korean economy, but nor is Kim Jong-un’s regime under real economic duress. Meanwhile, Pyongyang has developed considerable skill in sanctions-busting, especially through the judicious use of front companies.

And so we come back to the military options. At one end of the spectrum, that just means strengthening deterrence against North Korean provocations, and making sure that Pyongyang understands that either direct use of a nuclear weapon or conventional adventurism under the cover of the North’s relatively small nuclear umbrella would be met with an appropriately costly response. One option would be to return US tactical nuclear warheads to South Korea. But Washington is reluctant to do that, not least because it would suggest that it’s ‘balancing’ North Korea as a recognised nuclear power. Similarly, notwithstanding Donald Trump’s remarks on the election hustings last year, Washington isn’t keen to see South Korea and Japan construct their own indigenous nuclear arsenals. That would open a Pandora’s box of proliferation worries both in Asia and elsewhere.

A second option would be to take direct steps against the North’s missile program, for example. A concerted effort of cyber warfare, electronic warfare and ballistic missile defence could slow the program. Slowing it beyond that might require provocative steps, such as pre-emptive attacks on launch facilities. But that option will become steadily more difficult as the North ‘hardens’ potential cyber targets and moves towards the greater use of mobile missile launchers—something it’s already doing.

A direct military attack on North Korea to degrade its nuclear and missile programs would be the most serious of all military options. In the long run, it’s probably the surest path to the end goal—but in the short run, Pyongyang would have available to it a set of response options that would do serious damage to both Seoul and, perhaps, Tokyo.

And that’s why some analysts have their fingers crossed that the situation can slide—however ungracefully—into a long-term relationship of nuclear deterrence between North Korea and the US. But is that really a tolerable outcome? During the Cold War, the Soviet Union endured a relationship with France under which Paris threatened to ‘rip the arm off’ the USSR and leave it a one-armed superpower. Would the US be prepared to endure a similar relationship with North Korea? To be honest, it’s a doubtful proposition. North Korea is not France. It’s a pariah state. Even leaving it as a long-term nuclear-armed actor is bad enough—because Pyongyang might eventually decide to sell key weapons technologies or actual devices to others. But accepting a long-term relationship of mutual vulnerability with such an actor is a more difficult proposition than it first appears.

In the meantime, the latest missile test can only sharpen worries in Seoul about a potential decoupling of the US from security on the peninsula. The South Koreans have long worried that the development of a North Korean ICBM capability would make Washington more hesitant to come to the South’s aid in any possible nuclear showdown with the North. Seeing the capability begin to unfold now will probably stiffen the sinews of those in Seoul who believe the country needs to look more to its own strategic resources for the long-term future.

That’s a gloomy picture, I know. Let me add just one more thought to make it a little gloomier: time is not on our side.