During Richard Nixon's first term, when I served as secretary of defense, we withdrew most U.S. forces from Vietnam while building up the South's ability to defend itself. The result was a success -- until Congress snatched defeat from the jaws of victory by cutting off funding for our ally in 1975. Washington should follow a similar strategy now, but this time finish the job properly.

Public support for the war in Iraq has followed the same course as it did for the wars in Korea and Vietnam: broad enthusiasm at the outset with erosion of support as casualties mount. The experience of those past wars suggests that there is nothing President Bush can do to reverse this deterioration -- or to stave off an "Iraq syndrome" that could inhibit U.S. foreign policy for decades to come.

As the Pentagon prepares to redeploy U.S. forces around the world, it should review its practice of setting up bases in nondemocratic states. Although defense officials claim that having U.S. footholds in repressive countries offers important strategic advantages, the practice rarely helps promote liberalization in host states and sometimes even endangers U.S. security.

The Bush administration contends that the push for democracy in the Muslim world will improve U.S. security. But this premise is faulty: there is no evidence that democracy reduces terrorism. Indeed, a democratic Middle East would probably result in Islamist governments unwilling to cooperate with Washington.

U.S. policymakers debate how to wield American power; foreigners debate how to deal with it. Some make their peace with Washington and try to manipulate it; others try to oppose and undercut U.S. interests. The challenge for the United States is how to turn its material dominance into legitimate authority.

No country can affect China's fortunes more directly than the United States. Many potential flashpoints -- such as Taiwan, Japan, and North Korea -- remain, and true friendship between Washington and Beijing is unlikely. But their interests have grown so intertwined that cooperation is the best way to serve both countries.

A new survey of public opinion on U.S. foreign policy shows that Americans are split in two along party and religious lines. Still, significant majorities are starting to come together based on discontent with the war in Iraq, U.S. standing in the Muslim world, and illegal immigration. Soon the grumbling may become too loud for policymakers to ignore.

The United States has done much to enable China's recent growth, but it has also sent mixed signals that have unnerved Beijing. More consistent engagement is in order, because the course of the twenty-first century will be determined by the relationship between the world's greatest power and the world's greatest emerging power.