President Obama is in Seoul at this moment, the third stop of his 10-day, four-nation tour. Symbolically, his itinerary traces a sweeping arc from south Asia—India and Indonesia—to the north—South Korea and Japan. His travels include stopovers in friends—and none in troublemakers. He is, to his credit, skipping Pakistan and China.

This is not a trip that he would have taken in the first days of his administration. Then, he had clearly turned his back on President Bush’s vision of democracy promotion. Instead, he tried to build cooperative relationships with authoritarian regimes, such as those in China, North Korea, and Burma. Last November, for instance, he went to Shanghai and Beijing with high hopes and expectations. He came back both humiliated and empty-handed.

The current trip to Asia is a recreate-the-alliance tour, made necessary because his outreach to hostile regimes in the region has flat-out failed. Events over the last two years demonstrate that his generous policies made hardline governments demonstrably more aggressive. It is no coincidence that Beijing started its multi-month temper tantrum in early December, just days after Mr. Obama left the Chinese capital.

In extraordinary strategic shifts, the Japanese, South Koreans, Indians, and peoples in the Asean bloc have looked to the United States—especially to Secretary of State Clinton— to counter Chinese belligerence. Anti-Americanism, once fashionable in the capitals of the democracies of South and East Asia, is rapidly disappearing.

In his first three stops on the tour, Obama has hit the right rhetorical notes. The issue is whether his administration will carry through with the hard work of creating an effective alliance. For instance, his administration has yet to establish working relationships in New Delhi across a broad range of issues, especially military ones. Today, it was reported that the president failed to clinch a strategically important free-trade deal with Seoul.

In Washington—especially the White House—there is still the notion that we cannot get too close to our friends because we do not want to provoke the Chinas and Pakistans of the world. Mr. Obama today met with Chinese President Hu Jintao for the seventh time of his presidency. He has sat down with no other foreign leader more often.

We still think we can be friends with everyone in the region. Yet with conflicts escalating around China’s periphery—from India to Japan—we will be forced to take sides in the not-too-distant future.

So, it’s time for Washington to shore up alliances, make new friends, and prepare for the turbulence that will come soon.

Mr. President, you were “shellacked” at home last week. Try not to get shellacked abroad. This is your chance for political redemption. Perhaps your last.

Gordon G. Chang is the author of "The Coming Collapse of China" and "Nuclear Showdown: North Korea Takes On the World." He writes a weekly column at Forbes.com.