WASHINGTON — Sen. Lindsey Graham, R-S.C., called Friday for a strong U.S. response to last week’s use of chemical weapons outside Damascus, urging multiple missile strikes aimed at destroying Syrian President Bashar Assad’s major military assets and rendering him largely powerless. While Graham, in a statement with Sen. John McCain, R-Ariz, said the attack could be done “in a limited way, without boots on the ground,” the breadth of the two Republican senators’ suggested action would significantly increase U.S. involvement in a two-year civil war in Syria that has left 100,000 people dead and sent 1 million refugees into neighboring...