Operative word is "DEALS" and not "TREATIES"......
Deals are temporary while a President is in power and can be undone easily by the next one.
Treaties, via our Constitution, can ONLY be 'permanent' unless written otherwise by being RATIFIED by Congress (I believe the Senate).....and MUST be read ahead of time and then agreed to by a vote. Presidents are NOT allowed to enter into a treaty with any other country without Congress being involved.
I believe that even a 'deal' over something as powerful as a 'nuclear' deal would have to be considered to be a 'treaty' if it were taken to court (and it would probably end up there) because Congress would have to agree to eliminate the sanctions that have already been put in place in order for the 'deal' to take place, and that won't happen......making the 'deal' null and void. Congress is letting Iran know ahead of time that unless Congress sees the 'deal', they can go to hell and back before they will get what they are expecting to get from this president, which is a free ride with no concessions.

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