Photographed here at the Udvar-Hazy Center, Air and Space Museum.
The SR-71 was the first real stealth plane which accounts for its unusual shaping. However in reality radar technology improved rapidly diminishing the effectiveness.
However it was so fast that at the time the maneuver in the event of a surface to air missile launch was simply to outrun it.
And it worked, because none of the 32 SR-71s were ever shot down in their 34 years of service.