Jan. 16, 2010 -- President Obama officially enlists former presidents Clinton and George W. Bush to lead an ongoing American effort to help Haiti recover from a devastating earthquake four days before. Clinton soon visits Haiti for a firsthand look at the destruction.
Feb. 5, 2010 -- Pays a second visit to Haiti after being asked by the U.N. secretary-general to coordinate all international earthquake assistance to the beleaguered island nation.
Feb. 11, 2010 -- Has two stents placed in his coronary artery at the Columbia Campus of New York Presbyterian Hospital after feeling discomfort in his chest.
The Associated Press contributed to this report.