Gray closed his article by saying, "There may be some show-stopping issues for SDI, but they certainly have not appeared yet." The only reason SDI's many problems have not yet stopped the "show" is the willful blindness of the producers, from President Reagan down.
Possibly the most serious technical problem of all may be the computer software required for Star Wars. Computer software experts, including those hired by the SDI office itself, have repeatedly made this point. One, David Parnas, even resigned over the folly of the idea and the refusal of the Defense Department to listen to reason.
The problems are not theoretical limitations on computers or software. The problem is that we could never trust the system. As Parnas has said, there is no way to know whether the system is free of catastrophic flaws. Thus, the vast resources thrown into Star Wars will have been wasted. Instead of making nuclear weapons impotent and obsolete, as the President originally proposed, we will be forced to pursue the arms race endlessly.