What does "legally binding" do good at all? There are no other laws other than the rule of the strength.
U.S. was strong for a long time. It did whatever it liked.
Now Russia restored some of its strength to the point it can show others that sometimes you have to listen to when a bear warns you (quite calmly and nicely first).
Many people (even Americans) claim U.S. is not a democracy. Every country has corruption to some degree. The only backing and staying power there is - is the force a country has and its willingness to use it to defend something.
U.S. was strong for a long time. It did whatever it liked.
Now Russia restored some of its strength to the point it can show others that sometimes you have to listen to when a bear warns you (quite calmly and nicely first).