Yes, the POTUS is the President. But the US Constitution is built upon the separation of Powers – between the President, the Congress, and the Judicial system (the Law).
The President had Congress behind him, in an almost unprecedented way, upon his election 6 years ago. Under his leadership his party has lost “control” of congress, and he is now acting in opposition to Congress. This is one reason Congress invited Netanyahu to speak, to provide a counterpoint to negotiations the President is conducting which specifically do not have the support of a majority of the American population, which many, myself included, deem wrongheaded and reckless, and which endanger the security of America and the world. In the American democracy we have not only the right, but the obligation, to make these views known, in an effort to influence and moderate the President’s decisions.
Further, the global Nuclear Non-proliferation treaty is a legal document.
The President does NOT have the authority to unilaterally change that treaty, which (if the reports are accurate) he is undermining in his negotiations with Iran at this point in time. If he then proceeds to execute an agreement with Iran without congressional approval, he will be acting in violation of the law, and will serve to further destabilize the world which was made a safer place through the execution of that Non-proliferation treaty.
Already other nations are positioning themselves for the new “treaty-violated” world Obama is creating. Exhibit A is the agreement the Saudi’s reached with North Korea.
Thus, while my discussion partner made a valid point, it is pointless. I fully support the President of the US, so long as the President is acting within the constitutional rights we elected him to exercise and also uphold. To the degree he is acting outside those rights, or violating them, we need to support the Congress and the Judicial branch even if it means opposing the President.
That is the nature of the balance of powers which is what, even more than presidential leadership, has made this country great.