The planes that won the Cold War are getting old. They pack as lethal a punch as ever, but like the baby boomer generation they protected, they are beginning to show their age. The electrical system of the Air Force's A-10 Thunderbolt, better known as the Warthog because of its ungainly tail-engine configuration, lacks the juice to handle modern radar and battle-management computers. Salty sea air has hastened the breakdown of the insulation in some Navy jets, causing scores of fires and prompting a program to install arc-fault circuit breakers. The Marines are seriously worried that they could run out of Harrier jump jets. There is no argument within the defense community that America needs a new family of military aircraft. The problem is money. Keeping one step ahead of the former Soviet Union has driven the cost of aircraft to astounding heights. The U.S. Air Force says that the "fly-away" cost of the first 10 F-22 Raptors, the last fighters designed to counter the So...