I think this. Prior to actually coming here and talking to Hawkeye, Loki's last trip here was a brief chat with Thor in a room and some relayed experience through the destroyer. From Loki's perspective Earth should be a walkover- he probably thinks we're not much more dangerous than we were back in 965 AD when Asguard last showed up. Honestly outside of select few we are a laughable joke compared to Asguardians- even Volstagg can take a blast from the Destroyer. To him (and presumably most Asguardians) guns seem as little a problem as the swords they had back then. Looking at it now it really seems like their intel on us was way, way out of date. That could be a flaw in being so long lived though- I imagine Asguard hasn't significantly advanced in thousands of years.Ted C wrote:The Chitauri obviously had not prepared for a weapon to be launched through the portal at them, at least not that early in the conflict. A glaring oversight, perhaps, but it seems that Loki is their only real source of intelligence about the Earth, and he has lead them to believe that it will be a pushover.
I think where it really goes wrong is Black Widow and Hawkeye. Just one scene where Widow's bullets didn't penetrate Chitauri armour or something to say that these guys are dangerous- we need someone/thing more than just the military- would have added a significant amount of threat to the Chitauri.