Ambassador Jon M. Huntsman, Jr.'s blog on Obama's trip: http://www.whitehouse.gov/blog/2009/11/15/presidents-trip-china

SHANGHAI — President Barack Obama sought a political balance today on his first trip to China, seeking help on urgent global problems while weighing if and when to raise concerns over human rights.

Obama's agenda began with talks with local politicians and, in one of the marquee events of his weeklong Asian trip, he held an American-style town hall meeting with Chinese university students.

The president's first stop in Shanghai was the tranquil grounds of the Xijiao State Guest House, where he met with the city's mayor for about a half-hour and had lunch.

"Both of the countries have benefited greatly from the progress we have made over the last two decades," Obama said as the two sides' vast delegations were arrayed in a giant meeting room. Among the dignitaries with Obama was former Utah Gov. Jon Huntsman Jr., the U.S. ambassador to China, who introduced the president — in Mandarin — at the start of the town hall meeting.

Thirty years after the start of diplomatic relations between the United States and China, the ties are growing — but remain mixed on virtually every front.

The two nations are working together more than ever on battling global warming, but they still differ deeply over hard targets for reductions in the greenhouse-gas emissions that cause it. China has supported sterner sanctions to halt North Korea's nuclear weapons program, but it still balks at getting more aggressive about reining in Iran's uranium enrichment.

Obama arrived in Shanghai late at night, in a driving rain, hustling through a phalanx of umbrella-holding dignitaries to reach his limousine. He was to end his day in Beijing.

China is a huge and lucrative market for American goods and services, and yet it has a giant trade surplus with the U.S. that, like a raft of other economic issues, is a bone of contention between the two governments. The two militaries have increased their contacts, but clashes still happen and the U.S. remains worried about a dramatic buildup in what is already the largest standing army in the world.

Amid all that, Obama has adopted a pragmatic approach that stresses the positive, sometimes earning him criticism for being too soft on Beijing, particularly in the area of human rights abuses and what the U.S. regards as an undervalued Chinese currency that disadvantages U.S. products.