TOKYO -- Declaring himself "America's first Pacific president," President Obama opened his trip to the region Saturday by asserting that the future of the U.S. economy depends more than ever on Asia -- and by pledging that China's growth will not come at the expense of its neighbors.

In speaking to an invited audience at Tokyo's Santory Hall, Obama offered only cursory remarks on human rights, an issue that will grow more prominent this weekend as he crosses paths in Singapore with the leader of the Burmese military junta and then heads to China. As a sign of how exhausting his trip has already been, Obama briefly stumbled over the name of the Burmese opposition leader, Aung San Suu Kyi.

Unlike in earlier speeches in Cairo and Berlin, Obama did not seem to be...