Avengers: Age Of Ultron - 32 Easter Eggs, In-Jokes And References
9. The Civil War Foreshadowing
When Stark convinces Banner that they need to continue the Vision project that Ultron initiated, bonding the body with JARVIS' consciousness (but randomly creating something else entirely, somehow), Captain America arrives just in time to try and thwart their efforts.
With Scarlet Witch and Quicksilver at his side, Cap faces off against Stark for the first time in physical terms with their rivalry and clashing ideologies over how best to deal with Ultron very much fore-shadowing the fiction over the Superhero Registration Act.
Stark's extreme approach and Cap's caution will again play out in the next Captain America film, and these are clearly the ideological seeds on which that will be based.