You keeop referencing a great point Plane. The vast majority of these "successful" countries need only spend a fraction of a fraction of their country's budget on their military or defense needs....specifically because of the U.S. & NATO. We're not supposed to be the global police, but countries, just like Belgium welcome and even expect it. That way, the vast majority of their budgets can go into social engineering & related programs.
No one wants to overrun Belgium, or any other country, because of the presence of the U.S. as well as NATO. Everyone saw what happened to Iraq, when they tried it. Of course now, with the new placating policies being put in place, countries like China, Russia, and North Korea feel embolden, especially when they see how ISIS can make such geographical gains, despite our "military presence"