XB-70 vs B-2

"Hobo" wrote in message
...

Would it have made more sense to have built the XB-70 instead of the
B-2? With its speed and high altitude ability the XB-70 would have had
much of the survivability of the B-2, perhaps at a lower cost. The XB-70
would also have been less vulnerable to technological change. A single
big advance in sensor technology could make the B-2 a sitting duck, but
the XB-70 will always have its Mach 3 speed to rely on. In terms of
cost/performance, wouldn't the XB-70 have been able to do the same job
at a lower price?

The SA-12 goes up to about 100,000 feet and does at least Mach 6. Think the
XB-70 could handle that?