Long after his retirement, Mr. Scowcroft remained a pillar of the Republican national security establishment. In the run-up to the 2016 presidential election, he joined more than 120 other Republican foreign policy veterans who crossed party lines and endorsed Hillary Clinton. Mr. Scowcroft said she possessed “truly unique experience and perspective” to “lead our country at this critical time.” He did not mention Donald J. Trump in his endorsement.But days after Mr. Trump’s election, the frail and ailing Mr. Scowcroft made an emotional appeal at an off-the-record Washington luncheon in his honor, calling on fellow Republicans, and Democrats, to put country above political party and accept posts in the incoming Trump administration, if asked to do so.“He needs you, your country needs you,” one attendee said, characterizing Mr. Scowcroft’s message. Other accounts said that he remained concerned that Mr. Trump was ill-prepared and unsuited for the presidency, but said that his appeal for public service was a classic reminder of a less partisan age, when presidents often reached out to experienced talent, regardless of party loyalties.Brent Scowcroft was born on March 19, 1925, in Ogden, Utah, the son of James and Lucile (Ballantyne) Scowcroft. He graduated from the United States Military Academy at West Point in 1947, joined the Air Force and envisioned life as a fighter pilot.But on Jan. 6, 1949, his P-51 Mustang developed engine trouble after taking off from Grenier Army Air Field in New Hampshire (now Manchester-Boston Regional Airport), and crash-landed. His injuries were not critical, but he assumed he would never fly again and considered other military career options.In 1951, he married the former Marian Horner. She died in 1995. He is survived by their daughter, Karen Scowcroft, and a granddaughter.