I'm going to repeat myself, but I think it's worth it.
1961, at age 4, I was watching the CBS Evening News with my dad when President Kennedy appeared on-screen, explaining his decision to cancel the XB-70 "Valkyrie" supersonic bomber program.
The space-age InterContinental Ballistic Missle era (ICBM) spelled the end of both long-range and supersonic bombers in development to replace the B-52 fleet. Although the XB-70 was designed to exceed Mach 3, it was no match for ICBM's launched from ground or orbital space platforms!
But Kennedy's decision included continued funding for limited construction and testing of the XB-70 concept from 1961 to 1963, with flight testing to begin sometime in 1964, because the plane was an absolutely phenomenal engineering design that could lead the way to commercial supersonic transportation.
My favorite uncle called the XB-70 a, "Bow-Wave Surfer", because the under-belly pan, that housed the six giant jet engines, was designed to ride the shock-wave that formed under the wings, like a delta-winged surfer!
I always get emotional whenevr I see a new video about this plane. I've always felt a special connection to it, having no idea that almost 60 years later online military/commercial aviation fans would discover and marvel at an aircraft I was sure I would never see again!