Leading Article: Carrots, sticks and North Korea

PRESIDENT Bill Clinton used D-Day to point to the dangers of nuclear proliferation. He was not being irrelevant. One of the lessons of D-Day is that if you do not stand up to a tyrant at an early stage - as the Western powers should have done in the Thirties - the price of doing so later can be very high.

North Korea, which is now edging to the top of Washington's agenda, poses a seemingly much smaller but in many ways more awkward challenge than Hitler. In pre-nuclear times the military power of a nation was determined largely by its economic strength, so governments could weigh up the odds before engaging in a confrontation. Nowadays small, poor states can pose incalculable threats by acquiring nuclear or chemical weapons.

The response of others must then depend less on calculations of relative military strength than on whether the government in question is rational. In the case of closed, isolated regimes, the calculation is extremely difficult, so the possibility of irrational behaviour cannot be safely ruled out.

This is the dilemma now posed by North Korea. It seems to be engaged in making a nuclear bomb in defiance of the Non-Proliferation Treaty (NPT), of which it is a signatory. There is no other credible explanation for its refusal to be inspected under the terms of the treaty. North Korea has now raised the stakes by saying that it would regard the imposition of sanctions by the United Nations as an act of war.

Since it has a very large conventional army and has promised to unite Korea before the end of the decade, it might invade South Korea and threaten to use nuclear weapons if stopped. Who would be brave enough to call such a bluff? And yet, as some experts suggest, it may be engaged in nothing more risky than a bit of posturing and nose-thumbing as a prelude to some form of peaceful arrangement with South Korea, in which case Washington is over-reacting.

This is the type of nightmare that increasingly haunts world leaders. Their response to North Korea will therefore be calculated for its effect on other would-be nuclear powers. Their dilemma is not enviable. If they do nothing, North Korea will build its bomb and give the green light to others to follow, thereby destroying the NPT. But if they confront it, they may drive it into a corner and tempt it to react irrationally, with the added disadvantage that sanctions would have little effect on its poor and relatively self-sufficient economy.

Carrots and sticks have already been tried, but there is no obvious alternative to looking for a more effective combination of the two. Neither walking away nor all-out confrontation seems to offer better options. The ultimate aim must be to persuade North Korea that it would be better off as a normal member of the international community. As President Clinton has said: 'We want them to become a part of our world.' The dangerous part is getting them there.