I think the general answer to your question is "no, with some exceptions". One of the exceptions is "If that's true, you must have been rich", which seems fine. "must have" shows that you are talking about a past situation, but if someone has just made a statement about a past situation you can question it with "if that is true", in reference to the statement.
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AnonymousSuppose a guy says: I am a good soldier and I did nothing wrong. I reply: If you really were a good soldier, you should have protected those people.This seems reasonable, so perhaps my first impression needs modification.