There was something special about the 60s in the US. Your comment implies you might not appreciate how absurd the SR-71 was. The F-35 is our latest fighter jet. It has a top speed of 1200 mph, the SR-71 had a top speed of 2200 mph. The F-35 is capable of operating at around 50,000 ft, the SR-71 was capable of operating at 85,000 ft. The F-35 has a self fueled range of about 1350 miles, the SR-71 had a self fueled range of 2,900 miles.

Look up aviation records and you'll find the SR-71. It even still holds the #1 spot for the fastest airflight (by a plane) ever. Basically, the SR-71 is old, but old doesn't mean antiquated. The 60s was the era that we went from knowing basically nothing about space, to putting a man on the Moon in 7 years (Kennedy gave his 'to the Moon' speech in 1962, first landing 1969), while we currently flail about trying to recreate it with a program lasting into the decades already. The SR-71 was another product of this era.