Benzema kick-started the France fightback with the equaliser after they went down to Mikel Oyarzabal’s goal before Kylian Mbappe sealed the win to hand Les Bleus the trophy.
The Real Madrid striker was also crucial in the semi-finals as he led the charge as France came from two goals down to beat Belgium 3-2.
"Karim is a crucial player, and he has proven over the course of these two matches that he has very obvious talent," Deschamps told reporters.
"It's there for all to see, he is really kicked on from what he has been showing at club level with Real Madrid, he's got that desperate will to win. He's here exactly to do that, and he's communicated a great deal with his teammates, I am very happy for everyone, but especially for him.
"He needed that, he's not going to play another four or five international competitions, at least I don't think so. It's not the most important trophy, but he did everything, and he was very significant for us when it came to coming here and winning the Nations League.
"It's important of course to have come from behind and equalised. I am personally very happy for Karim, that's why he is here. He scores a bucket-load of goals with his club and he does likewise for France, and besides the goals that he scores... he has that wonderful will to win, and you can see that come out.
"I am delighted as for the future of course, it is very important, besides the talent that he or other players might possess, there also this mental strength he's got this competitive edge which is absolutely crucial at the highest level."
Benzema has now scored 33 goals in 92 caps for France.
