The fact that we only went for Benzema and Cavani suggests Wenger was happy with what he had rather than acknowledging the need for a better striker than Giroud, and should have been sent his scouting network to scour the continent and possibly others to make sure that we had it covered.
No one is advocating what United have done with Martial, I don't necessarily think it's a panic buy but who knows if they have done their homework to ascertain whether he will prove to be worth the gamble or will be the next Freddy Adu.
There is an issue of valuation, if a club values a player higher than Wenger values him than we won't do a deal, that is ridiculous....