"Well, it's prudent to do it, isn't it?" McMaster told Fox News' Chris Wallace on "Fox News Sunday," adding that "the president has asked to be prepared to give him a full range of options to remove that threat the American people and to our allies and partners in the region."
On Saturday, Adm. Harry Harris, commander of U.S. Pacific Command, redirected the USS Carl Vinson strike group from Singapore to the Sea of Japan, due east of the Korean Peninsula. The Navy said the strike group "will operate in the Western Pacific rather than executing previously planned port visits to Australia."
The strike group consists of the aircraft carrier USS Carl Vinson, the guided missile destroyers USS Wayne E. Meyer and USS Michael Murphy, and the guided missile cruiser USS Lake Champlain.
North Korea has already conducted four missile launches this year, marking a considerable uptick in frequency compared to recent years. The U.S. government and its allies have repeatedly condemned North Korea's nuclear and missile program as illegal.