10 Worst Things The Avengers Ever Did
4. Starting A War With The X-men
Proving that the trait lacking most in the Avengers is diplomacy, this brutal war between mutant and Avenger takes place because Captain America is mad the X-Men won't hand over Emma Frost, which is sort of like being arrested for not letting someone steal your children.
Although the scenario is a dangerous one, it doesn't quite warrant instigating an invasion - and then all-out war - when realistically the two teams could have worked together instead. Launching into a series of brutal battles is probably the worst decision the Avengers could have come to, especially when it forces the X-Men to appear like lawless criminals for not wanting to be randomly kidnapped - an accusation they've been forced to contend with for years.
The X-Men are - all fancy schools aside - another superhero team, and so the Avengers willingly warring with them instead of working together is a pretty unheroic move no matter how you look at it.