On the other hand they could be right.

If it ain't broke don't fix it.

The American system may not be perfect according to other people's lights; or quite visible patent obfuscation.

However, when one is dealing with ostensibly the most powerful man in the world, is remains almost impossible to go behind his back to arrange a countervailing deal?

Besides, he is just not a one man show and listens to and sometimes takes mind changing advice.

Which is likely more than one can say for any of the tinpot potentates he is currently trying to forge a workable deal with; and who can be completely relied on to honor their words to an infidel!? Hopefully, occasionally!?

Personally, I don't think the real problem lies with the (lame-duck) American President; given his agreements may still have to be ratified by the Congress; which by the way, could be hostile to his every (lame-duck) idea!?

So and ultimately, what does it matter who or how many are deciding American foreign policy?

What matters is that a workable deal is first struck and then completely honored on all sides; like say the habitually compromised, (middle east normal) two state solution between Israel and the Palestinians!
Rhrosty.

The writer has not mentioned that a Presidential Veto can be overturned by a 2/3rd vote in both houses and that around 10% of Presidential Vetoes have been overturned.

Also the Netanayu victory in Israel will convince the Senators that they are right to oppose the most pro-Muslim, anti-Israeli president ever elected.

With his repeated trashing of procedures O can't complain when there is a blow-back. In fact it is incumbent on those brave 47 who support separation of power procedures to make the most racist President in history understand it is not an elected Monarchy or for-life job like Mugabe.