Ok, I'm a bit confused.....
Why can't you buy a new .44 Mag? As far as I know, S&W is still making them. What you cannot do is buy a new made gun made the same way they made it 30 years ago. IS this what you mean?
The Clinton-S&W agreement went away with the Clintons, and with the change of ownership of S&W. If you are talking about the models of S&W that are made with the "hillary hole" locks, that is a decision of the current parent company. This company is the one that designed the lock S&W uses, so I don't think it is going to go away anytime soon.
Pres Bush cannot "terminate" the Clinton-S&W agreement, because it no longer exists as anything other than a sad piece of S&W history. They still make (some) guns with locks, because they believe it is in their best interests (politically and economically) to do so. Until the market (us) changes their minds, it won't change.