That's significant for a couple of reasons. Firstly, the NIF is now home to the world's first 2-megajoule UV laser. In and of itself, that's remarkable. But it also proved that it can surpass its own 1.8-megajoule design parameters without, you know, melting down or exploding or whatever super-powerful lasers do when they test to failure. This allowed it to fire a second shot just a day and a half later, another significant feat.