I remember thinking that Reagan was "over the top" when he proposed Star Wars---but he was right.
Dave, I spent 8 years working on "star wars" related programs (I/R sensors for missile defense). While I won't discuss classified details, I can assure you that these systems will work as advertised if properly funded and deployed. The test results are there to prove it. The Navy Aegis system is just one example of operational anti-missile systems that are working right now.