That depends on what you consider strong.
America's politics aren't a great thing in my eyes. They use propaganda to elude their people. There is a lot of secrecy of their inner workings. The same leader has been in post for a very long time, causing public outrage, yet nothing was done about it. Public surveillance is normal, accepted and encouraged. Assassinations of those who think differently are carried out. There is little to no respect to other, smaller countries from America's part.
Is it a strong system? Absolutely, the government possesses great power. Is it right, and something to be encouraged? I don't think so.
Of course, America has natural resources which puts them at an advantage, too. But i believe that influence is being used badly, which might change if the politics were handled differently.