Ever since his near-death experience against the Chitauri in The Avengers, Tony's number one priority is protecting the Earth against future alien assault.
It is shown through several films of the MCU that Tony Stark and his father, Howard Stark, had a strained relationship.
A clear example of this is that several villains, from both the Iron Man films and beyond, have a personal grudge against Tony and hate him specifically.
Tony has something of an unhealthy relationship with alcohol. He is often shown pouring himself drinks at times of stress.
He is depicted as very understandably in pain after learning that Steve, a close friend, knowingly protected Howard and Maria's killer.
There is no denying that Tony can be a hard person to like. Despite his immense charisma, he is erratic, and especially in early films heavily focused on himself.
From simple mechanised armour in Iron Man to the nanotechnology of Avengers he is consistently outmatched by other people in terms of power levels in the MCU.
Despite living much of his life as a confirmed bachelor, Tony Stark finds himself in fatherly situations more and more often as the MCU progresses.
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