The main idea of Henry's speech is to try to put a stop to an unnecessary confrontation between the British and the colonies.

Answer and explanation:

Henry's speech is to try to put a stop to an unnecessary confrontation between the British and the colonies. This is a false statement as Henry's speech main reason at the Virginia Convention, was to persuade his men to declare war to the British as he despites colonial rules since he thinks these are imposed ideas of subduming.