Seriously, why did they take this scene from the final cut? It is so very important! And not only to explain why Steve lacked the cowl in the end of the movie, but because this tiny moment is extremely important to Steve’s development as a character. He came to be seen as a fascist, as exactly that which he fought to destroy. Captain America, who sought to fight bullies his whole life, is now seen as one. Imagine the impact that had on his head. The meaning of his actions after he saw this. Steve began to give up the Captain America identity right here. This is why in Civil War he has no problems giving up the shield. He and Captain America have long been drifting apart. In fact, they were never one to begin with:
Steve went through his whole life trying to show people he wasn’t what they thought of him. Becoming Captain America was one way to do it, and giving this identity up is another one.
Steve isn’t unaware of the symbolism Captain America entails. For good and for bad. In The First Avenger he uses the symbol in his favour, transforming it. In The Winter Soldier he owns the symbol he became, working in favour of the greater good through his public image. However, in Civil War he has to give the symbol up, for it has come to represent something he is not.
When Tony tells him he doesn’t deserve the shield, Steve is tired of having to “prove” that his actions are those of Captain America. People put Captain America in a box that doesn’t fit Steve Rogers. Tony tells him he is not worthy of being Captain America, of carrying the shield his father made, as if he had betrayed what Howard Stark worked for, as if somehow Howard was responsible for the making of Captain America, and Steve became unworthy to be part of Howard’s legacy. This is just one way people created a general idea about who Captain America is, forgetting the man behind the shield.
Steve will be that which he has to be. That which he feels in his heart and head to be his duty, the right thing. He became Captain America for that reason, and for that same reason he threw cowl and shield aside.
Oh, this pisses me off that it didn’t make it onto the movie.