Le Pen has expressed support for Syrian President Bashar Assad in the past, and said on France-2 television Friday that she was "surprised" by Trump's sudden move, AP reported.
Le Pen said that Trump indicated he would not make the US "the world's policeman, and that's exactly what he did yesterday."
She warned that past international interventions in Iraq and Libya have led to rising extremism.
she made the comments after US launched 59 Tomahawk cruise missiles at the Syrian military airfield in Ash Sha'irat near Homs late Thursday. US President Donald Trump said the attack was a response to the alleged chemical weapon use in Idlib on Tuesday, which Washington blames on Damascus.