President Trump Tuesday received a briefing on options for attacking North Korea.
From the White House:
This morning President Donald J. Trump met with members of his national security team to receive a briefing from Secretary of Defense James Mattis and Chairman of the Joint Chiefs of Staff General Joseph Dunford. The briefing and discussion focused on a range of options to respond to any form of North Korean aggression or, if necessary, to prevent North Korea from threatening the United States and its allies with nuclear weapons.
Note the final line, which suggests the possibility of preemptive action.