Michele Bachmann lambasted President Barack Obama's foreign policy as his presidency's "worst act" in an interview Sunday on CNN, saying that critiques of it may open the door to effective attacks by Republicans in the general election.

"[The GOP candidates] understand foreign policy," Bachmann told CNN's Candy Crowley in the interview on "State of the Union." "Probably President Obama's worst act as president has been on foreign policy. That hasn't begun to have the level of scrutiny that it needs to have."