Captain America: Civil War
The United States Secretary of State Thaddeus Ross tells the Avengers that the United Nations (UN) wants to pass a law called the Sokovia Accords to control them, because there have been a lot of Avengers-related accidents that have killed innocent people. Ross tells the Avengers that they have to sign the Accords or become criminals, and if they sign it, the Avengers will have to listen to the UN and can't make decisions by themselves anymore. Tony Stark/Iron Man is at the meeting and tells everyone that he supports the Accords because he created Ultron, a program that went out of control and killed a lot of innocent people. Steve tells everyone that he doesn't support the Accords because politicians can be evil, and he wants the Avengers to make their own decisions.