We didn't flee Vietnam. We left in an orderly manner in 1972 after defeating the Viet Cong and NVA and forcing them to sign favorable peace accords.
Don't confuse film clips of evacuating our embassy in Saigon three years late as "we fled".
We won that war, pure and simple, and left. Later the Democrats refused to fund an enforcement of the peace accords and the communists were allowed to overrun much of S.E. Asia.
A minor technicality. By refusing to aid our sworn allies the South Vietnamese (thanks to Ted Kennedy and others), the appearance uf us fleeing the scene is all the more real.