From McClatchy's Jonathan Landay ...

The presumptive Republican nominee for president and the leading contender for the Democratic nomination are exaggerating what's known about Iran's nuclear program as they duel over how best to deal with Tehran.

Sens. John McCain, R-Ariz., and Barack Obama, D-Ill., say that Iran is developing nuclear weapons.

The U.S. intelligence community, however, thinks that Iran halted an effort to build a nuclear warhead in mid-2003, and the U.N. International Atomic Energy Agency, which is investigating the program, has found no evidence to date of an active Iranian nuclear-weapons project.