Jozy Altidore exited the United States' World Cup opener against Ghana with a hamstring injury, leading to a pretty ridiculous outcry from a certain subset of USMNT fans: "This is what you want Landon Donovan in the team for!"
Except this isn't what Landon Donovan would be in the United States team for if he had been picked ahead of Chris Wondolowski, Brad Davis or Julian Green. He's played as a central attacking midfielder, second striker or winger for the USMNT. It's extremely rare that he leads the line, for them or the LA Galaxy. He's not a target forward and he's never been a true No. 9 of any kind.
The United States doesn't have a direct Altidore replacement, but Donovan is even less of one than Aron Johannsson -- the man who replaced Altidore -- or Wondolowski. He could potentially be a Dempsey backup or a change of pace player on the wing, but he wouldn't come in for Altidore if he was in this team. He's too similar to Dempsey. It doesn't make any sense.
If Dempsey goes down, we can have a conversation about whether or not Donovan should have been in this team, but Altidore's injury doesn't change anything at all. He's just not that kind of player.