SEOUL—The U.S. sent two B-1B bombers to the Korean Peninsula to practice “attack capabilities” with South Korean jet fighters Friday, the latest show of force by the U.S. military following North Korea’s first-ever intercontinental ballistic missile test launch last week.

The joint exercise, which included U.S. F-16 fighters jets as well as fighter planes from the South Korean and Japanese air forces, came a day after U.S. President Donald Trump said in Warsaw on Thursday that he was considering “some pretty severe things”...