The point I want to emphasize here is that this is an executive agreement, not a treaty, so it does not fall under the process established under the Constitution. What is the difference between the two? Apparently the only distinction is what the president chooses to call it. Doing so then determines the role that the Senate plays in the deal.
The following Washington Post article discusses the rise of executive agreements:
- Here's the article: Can Congress stop the Iran deal?
. . . getting 67 senators to agree on complex international negotiations is difficult. So in the 1930s, President Franklin Delano Roosevelt figured out a workaround: He simply wouldn't call his international negotiations treaties. There, problem solved. His "executive agreements" could now unilaterally be approved by him and only him.
"When is a treaty not a treaty?" Stevenson said. "When it's not called a treaty." Otherwise: "There's no other difference."
Naturally, other presidents picked up on this politically convenient avenue. According to some statistics, executive agreements are now signed in the United States more than treaties -- by a ratio of 10-to-1. (Also: In the eyes of international law, there's no difference between the two.)
"That's the way the presidents have been since at least FDR," Stevenson said. "If they think they can get away with it, they'll do an executive agreement."
In the 1960s, Congress caught on to this sly move and passed a law requiring presidents to notify the legislative branch of all executive actions signed. But that didn't really stop presidents from making treaties and calling them by another name. It just meant they had to give Congress notice.