OIL-SPILL/ 

To underscore how seriously he is taking the BP oil spill in the Gulf of Mexico, President Barack Obama has chosen to make his nationwide address on the environmental disaster his first speech from the Oval Office, a setting presidents typically reserve for the gravest occasions – President George W. Bush spoke from there after the September 11 attacks, President Bill Clinton announced air strikes on Iraq, and President Ronald Reagan chose the Oval to talk about the explosion of the space shuttle Challenger.