During his visit to Asia this week, Colin Powell can expect Chinese leaders to speak bluntly, and the U.S. secretary of state will need to speak plainly in return.

What is most needed is a frank discussion about China's relations with North Korea, Taiwan and Japan. First, Mr. Powell should warn Beijing that its political, economic and military support for North Korea in its quest for a nuclear weapons capability belies Beijing's claims that China values a denuclearized Korean peninsula. Second, Mr. Powell will need to remind Beijing's leaders that the level of U.S. arms sales and military exchanges with Taiwan are linked to the level of threat China poses to Taiwan. And finally, Mr. Powell must caution China not to test America's commitment to Tokyo with illegal incursions into Japanese waters.

It is time Mr. Powell spoke candidly about America's disappointment with China's stance toward North Korea. Beijing's public statements and economic-aid policies have bolstered Pyongyang's position and undermined Washington's. The so-called six-party-talks framework for dealing with North Korea's nuclear-weapons ambitions has been underway for over a year, and has yielded zero progress. Instead, the situation has deteriorated. North Korea has claimed -- credibly -- that it has reprocessed spent nuclear-fuel rods into weapons-grade plutonium.

During this time, China has lavished economic aid on Pyongyang, and continually praised North Korea's leaders for their contributions to stability in the region and to world peace. China's continuing and generous stream of aid relieves North Korean leaders of the burden of choosing between saving their economy from collapse and developing nuclear weapons.

China's unwavering political, rhetorical and economic support for North Korea contrasts starkly with Beijing's attacks on Washington's policies. Immediately after the first round of six-party talks in August 2003, Chinese Vice Foreign Minister Wang Yi told journalists that "the American policy toward DPRK -- this is the main problem we are facing." Chinese sniping at the U.S. position continued unabated this year.

On June 6, Chinese Foreign Minister Li Zhaoxing even questioned American assertions that North Korea has a uranium-enrichment program. The existence of a North Korean uranium-enrichment program is at the core of American charges that North Korea violated the terms of the 1994 Agreed Framework, and the U.S. intelligence that led to those charges were bolstered by interrogations of Abdul Qader Khan, the Pakistani nuclear-weapons chief who admitted he sold an entire fissile uranium production cycle to North Korea after 1995. Moreover, U.S. Vice President Dick Cheney briefed Chinese leaders on the North Korean uranium program during his visit in mid-April. China's public failure to acknowledge the facts is a sure sign it is not interested in pursuing the type of "body-cavity search" inspection regime that would be required for a complete dismantlement of the North's weapons programs.

The second area where a U.S.-China dialogue needs straight talk is Taiwan. Maintaining a defense relationship with Taiwan was an explicit condition of U.S. normalization with China in 1979, and the survival and success of Taiwan's new democratic government is in Washington's interest. Taiwan is one of America's top 10 export markets and a key defense and intelligence partner. As such, it has been a consistent U.S. policy that Taiwan's political status may not be changed except with the explicit "assent" of the people of Taiwan.

China apparently feels that military posturing will induce the U.S. to back away from its support for Taiwan. Over the past four months, China has demanded the so-called "Three Stops" -- that the U.S. ends all arms sales, official encounters with Taiwan and support for Taiwan's role in international organizations. In the meantime, China has increased its missile deployments, expected to reach an estimated 600 by the end of 2004 from 500 in 2003. More disturbing, defense sources in Washington have said that China has dramatically increased the number of jet-fighter sorties along the "center-line" of the Taiwan Strait in recent weeks.

In confronting Chinese demands that Washington abandon its defense support for Taiwan, Mr. Powell should restate that it has been U.S. policy for 25 years to sell arms to Taiwan, and that the U.S. could not have normalized relations with China in 1979 unless this was clearly understood. He might also repeat patiently, as President Ronald Reagan declared in 1982, that the level of arms sales is "conditioned absolutely" upon the continued commitment of China to the peaceful solution of the cross-strait differences.

Finally, Mr. Powell should remind his Chinese hosts (in the words of Assistant Secretary of State James Kelly) that Washington's "one China policy" is not the same as Beijing's "one China principle." He should make clear that Washington's policy must not be misinterpreted as an acknowledgement that Beijing has any right to use force against Taiwan. According to Mr. Kelly, America's policy is that Beijing should renounce the use of force toward Taiwan, and that both sides should "pursue dialogue as soon as possible through any available channels, without preconditions" and "on an equal basis."

China's aggressiveness in East Asia is not limited to Taiwan. Chinese maritime vessels are pushing the envelope in Japanese waters in the East China Sea. Mr. Powell must therefore be prepared to caution China against giving official permits to Chinese oil-exploration ships to begin resource surveys in Japanese waters near Okinawa and the Senkaku Islands, known in China as the Diaoyu Islands. Chinese oil exploration in Japan's exclusive economic zone is designed to probe for weakness in the U.S.-Japan Mutual Security Treaty.

Mr. Powell must be prepared to repeat clearly the U.S. position that the Senkaku Islands have been under Japanese administrative control since they were returned as part of the reversion of Okinawa in 1972. He should leave the Chinese in no doubt that the U.S. will support its most important ally in Asia, just as Japan has supported Washington in the war against terror.

In these important foreign-policy matters, a candid, clear dialogue between Washington and Beijing is essential if both sides are to avoid stumbling into a crisis.

Mr. Tkacik, a research fellow at the Heritage Foundation in Washington, D.C., is a retired officer in the U.S. foreign service who served in Beijing, Guangzhou, Hong Kong and Taipei.