Working as a pundit for Sky Sports, Henry suggested Arsenal were four big players short of the quality required to win the league and singled out Olivier Giroud in particular as not being up to standard.
Per the Guardian's Amy Lawrence, Wenger responded:
I think he's wrong. He's paid for that. We know all the system now of the modern media, especially on TV. I know how it works. They push you to be controversial because they give you a lot of money.
I can accept an opinion but the comment on Giroud was a bit more wrong, especially because I heard the same thing being said about Nicolas Anelka, about Thierry Henry himself and about Robin van Persie. And they all became world-class players themselves.
I think they need to buy four players—they need that spine. They need a goalkeeper, they still need a centre back, they still need a holding midfielder and, I'm afraid, they need a top, top quality striker to win this league again.
I think Giroud is doing extremely well. But can you win the league with him? I wouldn't think so. He does a job, and he does it ever so well, but you can't win the league.
Does Henry have a point about Giroud? Yes and no.
Despite breaking his foot in August, which kept him out until the latter half of November, the Frenchman has scored 17 goals in all competitions this season, as well as making three assists, per WhoScored.com.
Without that injury, the 28-year-old would likely be contending with Diego Costa, Harry Kane and Sergio Aguero's goal tallies.
To give further context, Eden Hazard, recently awarded Player of the Year, has the same number of league goals—14—but has spent more than double the amount of time than Giroud has on the pitch, according to Squawka.
While the Frenchman may not be blessed with Aguero's incredible pace or Costa's raw brute force, Giroud is powerful in the air and possesses excellent technical skills, which allow him to participate ably in Arsenal's excellent link-up play.
Perhaps the finest example of what Giroud brings to the team can be seen in the crucial and magnificently executed one-two with Jack Wilshere in the latter's famous goal against Norwich, one of eight assists he managed last season (h/t WhoScored.com):
However, it is plain to see that Arsenal do need more firepower up front if they are to genuinely challenge for the league.
Alexis Sanchez is the only other Gunners player to reach double figures in the league this season, while Danny Welbeck has just four.
Alone, Giroud cannot win the league for Arsenal, but had the likes of Welbeck and Arsenal's other supporting players chipped in with more, the title race would have at least been much closer.
Since Welbeck is simply not prolific enough, Henry is right; Arsenal need another striker in the summer.