Whether Congress approves or not remains an unknown, and even if this agreement is signed, it could still be torched by its own back yard.

Rubio testified at a congressional hearing that the U.S. is still negotiating with Iran, and it is uncertain when an agreement will be reached. Iran has agreed to negotiate on some issues related to its nuclear program, a change from a month ago. An agreement could be reached on that day, tomorrow, or next week, but there is no guarantee it will be approved by Congress. The U.S. has not proposed lifting sanctions or using frozen funds as conditions; any sanctions relief must be contingent on resolving Iran's nuclear program.