Which conflict from The Tragedy of Julius Caesar is not an example of external conflict?

In the first act of The Tragedy of Julius Caesar, Marcus Brutus is confronted with an internal conflict in which he has to decide whether to support his good friend, Julius Caesar who wants to become the King of Rome or the interests of Rome as a nation. He realizes that if Caesar becomes the leader, there will be ruthlessness and in a loyalty to his country, joins a conspiracy to assassinate his friend.