Barack Obama actually said...

"If those efforts fail, then the U.S. will not participate."

"I will do everything in my power to prevent Iran from obtaining a nuclear weapon--everything in my power to prevent Iran from obtaining a nuclear weapon--everything."

"while we should take no option, including military action, off the table, sustained and aggressive diplomacy combined with tough sanctions should be our primary means to prevent Iran from building nuc..."

"We should also pursue other unilateral sanctions that target Iranian banks and Iranian assets."