Former secretary of state Condoleezza Rice says that American leaders need to resist the temptation to become weary of war, according to a report of her remarks at a fundraiser.

“I fully understand the sense of weariness," she told a GOP fundraiser Wednesday, according to reports. "I fully understand that we must think: ‘Us, again?’ I know that we’ve been through two wars. I know that we’ve been vigilant against terrorism. I know that it’s hard. But leaders can’t afford to get tired. Leaders can’t afford to be weary.”

President Obama has made clear in recent weeks that the Russian incursion into Ukraine's Crimean peninsula doesn't yet call for military intervention, and unlike the conflict in Syria, Obama hasn't broached the concept of using force in Ukraine.

As with the conflict in Syria, polls show the American people are highly resistant to military action in Ukraine -- especially after lengthy wars in Iraq and Afghanistan.

Rice said the United States has taken a step back in conflicts including Syria, Ukraine and others.

“When America steps back and there is a vacuum, trouble will fill that vacuum," Rice said.