(AP) - In his first trip abroad since the summer heat of the re-election campaign, President Barack Obama will seek to reinforce American influence in Southeast Asia in spite of the large shadow cast by China. Obama will become the first U.S. president to visit Myanmar, an appreciation for its steps toward democratization, as well as Cambodia. The four-day trip that began Saturday will be the president's fourth to Asia. Obama is eager to return to foreign policy matters that were put on the back burner by the campaign. The unprecedented visit to Myanmar, also known as Burma, gives the trip a historic edge while shoring up a strategic regional goal sought with stops in Thailand and in Cambodia, where he will attend the East Asia Summit.