Even as it girds for war in the Persian Gulf, the Bush Administration faces a major challenge in East Asia - that of a nuclear North Korea.

The conflict emerged quite suddenly. Back in October, Pyongyang stunned the White House with its unexpected admission of an active clandestine nuclear program.  The disclosure was followed, in rapid succession, by the DPRK's December decision to restart its Yongbyon nuclear facility and expel International Atomic Energy Agency inspectors.  A month later, North Korea abruptly withdrew from the 1968 Nuclear Nonproliferation Treaty and rolled back its self-imposed 1999 moratorium on missile testing.  Together, these moves have presented Washington with an unprecedented - and escalating - problem on the Korean Peninsula.

The current crisis holds important lessons for the Bush Administration.  First, North Korea's nuclearization has eloquently exposed the dynamics of contemporary proliferation. The DPRK's active strategic partnerships with Pakistan and Iran, and the significant contributions of both countries to Pyongyang's atomic efforts, are a test case in how to acquire ballistic missiles and weapons of mass destruction (WMD). North Korea's nuclear successes, in turn, mean that other aspiring weapon states are bound to try and follow in its footsteps.

Second, the present dilemma in East Asia is likely to foreshadow far greater trouble ahead. After years of neglect, North Korea has emerged as the world's leading proliferator, actively exporting missile and WMD technologies to countries in the Middle East, Africa and Europe. With increasing urgency, U.S. officials now raise concerns about the detrimental effects of the DPRK's ongoing proliferation on long-term security in those regions. Given this established strategy, policymakers in Washington justifiably worry that it could only be a matter of time until North Korea's newest commodity - its nuclear capability - becomes an export item.

Third, Washington's Pyongyang problem emphasizes the shortcomings of arms control. The diplomatic approaches adopted by the Clinton Administration during the 1990s, most prominently the now-defunct 1994 "Agreed Framework," may have achieved a modicum of political success. But as nonproliferation tools, they constituted spectacular failures. Not one addressed the strategic importance assigned by the Kim regime to its unconventional weapons capability, instead assuming the DPRK's ballistic missile and nuclear programs to be bargaining chips. Even worse; by repeatedly offering an array of economic and political incentives in spite of proven North Korean noncompliance, U.S. policy enshrined in Pyongyang the notion that rogue behavior reaps rewards.

Finally, North Korea's nuclear breakout has suddenly given it significant leverage over Washington. Its emerging nuclear capability, together with its existing arsenal of intercontinental ballistic missiles, has created a capacity to credibly threaten the United States and its deployed forces.  As a result, the DPRK now has the ability to limit not only the administration's response to the current conflict, but severely constrain Washington's larger freedom of action in Asia as well. Moving toward an effective strategy requires eliminating this potential for nuclear blackmail.

Significantly, a similar understanding seems to be emerging in Asia, where growing worries over North Korea have galvanized an unexpected consensus about the need for missile defense. Japan, for example, recently opted in favor of a dramatic expansion of missile defense ties with the U.S., long limited to simple research and development. South Korea has quietly adopted an analogous approach: despite their government's enduring commitment to a "sunshine" policy for the Korean Peninsula, and notwithstanding a growing popular anti-Americanism, defense planners in Seoul are working with Washington to craft a common missile defense strategy in response to Pyongyang's expanding capabilities. Taiwan, menaced both by North Korea and by a mounting missile threat from China, is meanwhile moving ahead with ambitious plans for a comprehensive national missile defense, while simultaneously exploring cooperation with the U.S. on the creation of a regional anti-missile architecture.

For Washington, promotion of these dynamics should make for sound policy.   Without adequate protection against North Korea's growing arsenal, the durability of America's Asian alliances could increasingly be called into question.  A practical regional defense, on the other hand, might do much to insulate Washington's international partners from Pyongyang's policies. And the benefits of such an approach will hardly be limited to the Korean Peninsula. Expanded anti-missile capabilities hold the promise of greater security for U.S. allies in the Middle East and Europe, already coping with the destabilizing regional effects of DPRK proliferation in their respective neighborhoods. At home, meanwhile, a national missile defense of the kind promised by President Bush in his landmark December 17th deployment directive remains the only effective answer to a nuclear North Korea.

The stakes in the current standoff are high: how Washington responds to Pyongyang's brinksmanship will ultimately have a profound impact on American security, as well as on the future balance of power in Asia. Any effective answer, however, must begin by neutralizing North Korea's ability to threaten the U.S. and its allies abroad. For both the White House and its Asian partners, missile defense constitutes the first step in that direction.

Ilan Berman is Vice President for Policy at the American Foreign Policy Council in Washington, DC.