Wilshere has been ruled out for up to three months after failing to recover from the ankle injury he aggravated during a pre-season game in July.
The original problem was sustained in the Euro 2012 qualifier between England and Switzerland in June.
And, faced with a lengthy injury list and the departures of Cesc Fabregas and Samir Nasri there are some at the Gunners who have voiced concern about the treatment Wilshere has received on England duty.
Capello does not understand the argument and is adamant there is no need to feel any remorse.
"When I selected him, he was fit," said the England coach.
"During a game, it can happen, it's normal. People get shoulder, knee, head injuries. Something can happen in a tackle. It happened.
"When he started the game he was fit. If he hadn't been, he wouldn't have played."