(TOKYO) — Facing fresh questions about his commitment to Asia, President Barack Obama will seek to convince Japan’s leaders Thursday that he can deliver on his security and economic pledges, even as the crisis in Ukraine demands U.S. attention and resources elsewhere. MoreObama Lands in Tokyo On First Stop in Asia TourTop Career Diplomat William Burns Will RetireMen Charged With Toppling Ancient Rock Formation Avoid Jail Time Huffington PostHere's An Updated Tally Of All The People Who Have Ever Died From A Marijuana Overdose Huffington PostAmy Purdy Shows Off Her Specially Designed 'New Feet' for Dancing with the Stars PeopleThe ominous standoff between Ukraine and Russia is threatening to overshadow Obama’s four-country Asia swing that began Wednesday.