Democratic insiders have concluded that President Trump is unusually vulnerable on national security for a Republican, an assessment based on extensive research, but warn the party’s leading 2020 contenders are squandering this unique political opening.

The crowded field of would-be White House nominees has been virtually radio silent on the range of threats facing the United States, from terrorism to illegal immigration to cyberattacks, preferring to to discuss domestic issues such as healthcare popular with the progressive base. Liberal foreign policy experts fear this failure to both acknowledge these key national security concerns, and offer contrasting solutions, could cede crucial political ground to Trump once the general election begins next year.