The question now is what makes these countries more powerful than others?
The term independence is one that comes with a lot of obligations for a people as having an ability of sole existence, produce more of what is needed for there survival and sovereignty or control over the happenings within it's nation state. This is where most nations have failed especially developing nations because, they've been unable to carter for its masses.
It isn't out of place to say one nation can't exist comfortably without the other due to the distribution of resources both human and natural but, having the tendency to depend more than normal on other nations for what you consume doesn't really make you dependent does it?
The dominance of a nation with respect to others relies mainly in there;
1. Economic power.
How stable is the economy, if they produce more than they import and don't depend more on importation.
2. There military power
This defines how secure is the state of the nation and what weapon they've got in there arsenal to defend the state in times of invasion. Needing foreign aids is you as well being subject to terms and not being in control.
Some nations would always be ahead or dependent on others, not because they far existed or gained independence before others but, there ability to harness there human and natural resources for the greater good of there nation state.