The YAL-1A is a converted Boeing 747 created by the Missile Defense Agency and outfitted with a chemical oxygen iodine laser. WSJ's Nathan Hodge reports.

Over the years, the concept of missile defense has been refined and reimagined ... and rejected would have mounted a powerful laser on a Boeing 747 airframe to zap missiles in the boost phase.

Gen. Dan Karbler told the audience at the virtual Space Missile Defense symposium on Tuesday The so-called “laser battalion,” as Defense One described it, would eventually deploy the new 50 kw ...