No. The Second Amendment protects your right to keep and bear arms. It doesn't address you buying weapons in another country - or even this one.
The sky is falling approach used by many people only undermines honest efforts to protect our rights when free-thinking individuals, who will take the time to read documents and think for themselves, spot the obvious hyperbole/BS and wonder what other lines they're being fed.
I have read portions of it and that is why I said the language is ambiguous.
Can you point me to the part of the treaty that says it will not regulate me buying a hunting rifle from Japan?