Trump 'celebrating undoing a problem he created'
On Thursday, Turkey agreed to a ceasefire in northern Syria to let Kurdish-led forces withdraw.
The deal came after US Vice-President Mike Pence and Turkey's President Recep Tayyip Erdogan met for talks in Ankara.
Turkey launched the cross-border offensive last week, after US President Donald Trump announced he was pulling US forces out of the Syria-Turkey border region.
Democratic Congressman and former Marine officer Seth Moulton spoke to the BBC.