That would be Vera Lynn. Honey, we’re all out of Kleenex.
(At the end of the clip Vera sings “We’ll Meet Again,” and the RAF boys sing along with her. That’s what really got the waterworks fired up.)
(And I note in passing that, making due allowance for the state of orthodentistry in 1940s England, Vera was a babe. My Dad had a major crush on her, and I see why.)