Donald Trump won the presidency by promising to lower costs and end wars. A year and a half later, he is a wartime president contemplating whether to send U.S. ground troops into an expanding conflict in Iran. Gas prices are spiking and Trump is urging Americans to be patient. Everything adds up to a perilous situation for Republicans in the midterm elections, which will determine control of Congress. The president did little to sell the war to skeptical voters before it started, and he defended his leadership on Wednesday night in his first major presidential address on the conflict.