There is no reason to believe that USA is a failed nation on any parameter. In fact it is THE place to be in this world. It is the land of opportunity for everyone. That is why people have been moving to the states and making their fortune. US is the country which is maintaining more and more world order is in fact is successful state.
America has always been a leader in any case, so it has become a destination for many activities such as economy, politics, culture, etc. With any parameters, America cannot be called a failed state, because its progress is followed by many nations in the world and innovations carried out by Americans can change the world for the better.