WASHINGTON, Dec 30 (Reuters) - A senior Republican senator said he would try to persuade US President Donald Trump at a White House lunch on Sunday to reconsider his order for a total US military pullout from Syria and leave some US troops there.Senator Lindsey Graham warned that removing all US forces would hurt US security by allowing Islamic State to rebuild, betraying US-backed Kurdish fighters battling remnants of the militant group, also known as ISIS, and enhancing Iran's ability to threaten Israel.The South Carolina Republican said he would ask Trump "to sit down with his generals and reconsider how to do this. Slow this down. Make sure we get it right. Make sure ISIS never comes back. Don't turn Syria over to the Iranians.""I want to fight the war in the enemy's backyard, not ours," Graham said in an interview on CNN's State of the Union show.Graham praised Trump, who visited US troops in Iraq last week, for announcing that a US force would remain there. But he said ISIS, while holding only slivers of territory, remained a potent threat in northeastern Syria."That's why we need to keep some of our troops there," he said.The Pentagon says it is considering plans for a "deliberate and controlled withdrawal." One option, according to a person familiar with the discussions, is for a 120-day pullout period.Graham, an influential lawmaker on national security policy who sits on the Senate Armed Services Committee, is an ally of Trump, although he has opposed some of his foreign policy decisions.