The cost of maintaining and repairing the fleet of U.S. F-35s has been set at $1 trillion. But facing increasing fiscal pressure, Congress is asking manufacturer Lockheed Martin to find a cheaper way. WSJ's Nathan Hodge reports from Washington. A new Pentagon forecast showing the total cost of owning and operating a fleet of F-35 Joint Strike Fighters topping $1 trillion over more than 50 years has caused a case of sticker shock in Washington. And that price tag doesn't even include the $385 billion the Defense Department will spend to purchase 2,500 of the stealthy planes through 2035. During...