[onewhippedpuppy]

Originally Posted by wdfifteen

Let me ask another way. How does ANYTHING move through the atmosphere at 27 times the speed of sound without being destroyed by friction before it strikes a target on earth?

The space shuttle was in the ballpark of Mach 25 upon re-entry. That was for a large glider with a manned crew and complex equipment. The million dollar question is how to quickly propel an object to that speed without putting it into orbit and at a practical cost. After that point kinetic energy takes care of the rest. KE is 1/2*mass*velocity^2, so that means that kinetic energy is an exponential function of velocity. We are talking about a glorified lawn dart moving very very fast that can do a lot of damage. And conventional defenses would be useless against it.