On Monday, a dozen Democratic senators sent a letter to President Trump about escalating tensions with North Korea. The lawmakers expressed their anxiety over reports that the White House is considering a preemptive military strike against North Korea, and additionally questioned the administration's decision not to nominate Dr. Victor Cha as the ambassador to South Korea because of his reported opposition to the aggressive position.

"According to some media reports, the real reason for Dr. Cha's removal [from consideration] was his disagreement with a 'bloody nose' [military strike] under consideration from the White House," the letter reads. The senators claim that it is an "enormous gamble" to believe any first strike by the U.S. would not provoke "an escalatory response from Kim Jong Un," adding that "a preventive or preemptive U.S. military strike would lack either a constitutional basis or legal authority."

The senators say that although they "may or may not agree with Dr. Cha on every issue," they were unsettled by reports that he had been properly vetted and all but approved by the South Korean government before his nomination was retracted based on policy disagreements. Given the escalating crisis on the Korean Peninsula, it is "shocking," the lawmakers wrote, that "the administration — a full year into its term — has yet to formally nominate someone" to be the ambassador to South Korea.

Among the signatories are former vice presidential candidate Sen. Tim Kaine (Va.) as well as expected 2020 Democratic presidential contenders Sens. Elizabeth Warren (Mass.) and Bernie Sanders (Vt.). Read the letter here. Kelly O'Meara Morales