These are the USS Abraham Lincoln and the USS John C. Stennis, two of the ten nuclear-powered Nimitz-class aircraft supercarriers in service with the United States Navy. The Lincoln just arrived to the Strait of Hormuz as tension keeps mounting up in the area.
She has joined the USS Carl Vinson as the USS John Stennis leaves to the Pacific, according to the Pentagon. It's nice that the Navy got to show off three carriers in the same area simultaneously, though. Not that Ahmadinejad and his cronies didn't know that the US had ten of these, but it's different to see the three of them right in your backyard than just knowing about them. I'm sure that made them a little bit uncomfortable.
The Strait of Hormuz is an extremely important geographic point. Forty percent of the world's oil passes through this strait on its way out of the Persian Gulf. Whoever controls this pass, would be able to inflict great damage to the world's economy.
According to the Washington Post, an Iranian lawmaker is now proposing to close the strait in retaliation against the oil embargo recently approved by the European Union, which has followed the United States in their sanctions against Iran's nuclear program.