Distancing herself from President Barack Obama's foreign policy, potential 2016 U.S. presidential candidate Hillary Clinton said in an interview Sunday that the U.S. decision not to intervene early in the Syrian civil war was a "failure."

Republican critics and others have faulted Obama for doing too little to support Syrians who rose up against President Bashar Assad. The Syrian conflict has raged for three years, with Assad staying in power and Islamic militants gaining strength among the rebels.

"The failure to help build up a credible fighting force of the people who were the originators of the protests against Assad — there were Islamists, there were secularists, there was everything in the middle- the failure to do that left a big vacuum, which the jihadists have now filled," Clinton said in an interview with The Atlantic.

Clinton was Obama's secretary of state during his first term as president, stepping down in early 2013, so she was part of the administration during the start of the Syria uprising. Seen as a strong contender for the 2016 U.S. Democratic presidential nomination, she ran unsuccessfully for the party's nomination in 2008.

Asked about Obama's slogan of "Don't do stupid stuff" to describe his foreign policy thinking, Clinton said, "Great nations need organizing principles, and 'Don't do stupid stuff' is not an organizing principle."

Clinton also offered strong support for Israel and for Prime Minister Benjamin Netanyahu., who has a tense relationship with Obama.

Questioned about whether Israel has taken enough steps to prevent the deaths of civilians in the Gaza war, including children, Clinton said the United States also tries to be careful to avoid civilian casualties in conflicts but sometimes mistakes are made.