The World Unites: The First War

Everything on Earth in SAO is perfectly fine and normal, then one day out if nowhere astroids fall out if the sky and crash Into earth and there is a giant ship in the sky, earth is being invaded, but by who? Tag along with Kirito and the others in a world where all of the countries in the world put aside their differences and decide to become one giant army to defend their planet against the invaders, will they succeed? Or will the invaders take over their planet? Stick around and find out