IMAGINE a poker game in which one of your opponents lays down a big bet, and you're so sure he's bluffing that it's very tempting to call him on it. But you also know he's packing a gun and, if you clean him out, he's just crazy enough to use that weapon. You're very well armed, but some of the other players at the table are much less able to defend themselves and are sitting much closer to this dangerous loser.

What a predicament. Do you call the lunatic's bluff and risk setting him off? Do you cave in, reward him with the pot and thereby embolden him to pull the same threatening stunt again and again? Or do you and the other players try to somehow find a way to call his bluff and disarm him at the same time?

This is pretty much the tough choice facing the United States -- and Japan, South Korea, China and Russia -- in dealing with North Korea's claim that it's been secretly working on building nuclear weapons.

That admission in September shattered a 1994 agreement with a U.S.-led consortium under which the North was supposed to freeze its nuclear program in exchange for shipments of heavy fuel oil and building two reactors to generate power. It also cast a lot of doubt on the wisdom of engaging -- not isolating -- the North through South Korea's "sunshine" policy and U.S. efforts to directly negotiate disarmament.

So the consortium has now cut off the North's badly needed oil shipments, unless it verifiably drops its nuclear program. These shipments reportedly have been supplying as much as 15 percent of the North's energy. Along with a drop in world food aid to the North, it points the failed, famished regime toward even more dire straits.

Then there's next month's South Korean presidential elections, in which a conservative opposition party could take office and roll back President Kim Dae Jung's five years of drawing the North into growing tourism, humanitarian and economic cooperation.

All this amounts to calling the North's bluff. Some analysts believe that will work because, in contrast to the last such Korean crisis in 1994, the North now has much more to lose. It now has food aid, diplomatic ties and economic links that it did not have then and that would certainly be jeopardized if it reacts aggressively.

At the same time, there's no predicting the North's actions. Millions in South Korea and even Japan are potentially in harm's way -- despite U.S. defenses. So this step to pressure the North must be carefully calculated so as not to leave it cornered, instead steering it toward peaceful resolution.

In an interview this week, South Korea's ambassador to the United States, Yang Sung Chul, stressed that a lot of patience -- based on a very long-term view -- is essential to resolving the present crisis.

As tempting as it would be to thoroughly isolate this frustrating and dangerous poker player, he's right: Patience -- and a creative but careful balance of threats and engagement -- must infuse U.S. strategy toward North Korea.