The part of British Common Law that states a person is innocent until proven guilty will do.

Please don't insult the Consititution by stating that the word "person" in that document means "citizen". The Founders knew the difference, as many of them were not native-born themselves.

I call your special attention to Amendment VI, quoted below in its entirety:

In all criminal prosecutions, the accused shall enjoy the right to a speedy and public trial, by an impartial jury of the state and district wherein the crime shall have been committed, which district shall have been previously ascertained by law, and to be informed of the nature and cause of the accusation; to be confronted with the witnesses against him; to have compulsory process for obtaining witnesses in his favor, and to have the assistance of counsel for his defense.

The greatness of America is fed by our economy, but is founded upon our ideas. This is one of them. If you think that to insist upon equal access to the great ideas upon which this nation is based is wrong, you need to reread your American history. The principle is important; it only lives if we practice it, regardless of whether its practice makes it "easier" to prosecute a war or not.

Please note that certain words in the Sixth have exact meaning as well: "all" in "all criminal prosecutions", and "the accused", which does not read "the accused US citizen" or "some of the accused".

You should be proud that officers of the court would volunteer to defend someone accused of a crime, any crime. American justice doesn't work without an able defense.