The London-based broadcaster for American networks said was "stunned" by British MPs voting not to take part in military action.
But she added: "Having covered wars, I also know that limited targeted strikes - no boots on the ground - are sometimes really necessary to end terrible, terrible, terrible, inhuman suffering."
In her personal film for BBC1's This Week, she claimed it was the "credible threat of US force" in Syria that forced the Syrians, with Russians, to discuss destroying weapons.