At any given time in modern history, a Greatest Country in the World, if it ever existed according to any realistic set of statistics, would hold that number one position only briefly. With how the world works now, all within an interconnected global economy, and to an increasing extent, global policies, there never will be a Greatest Country.
Touting your country's greatness can be as benign as team pride, or as toxic as genocidal imperialism. Probably best to just forget the whole jingoistic Greatness obsession and focus instead on enlightened self interest through joint projects with other nations.
All any nation can aspire to is to be a decent fucking neighbor in the global neighborhood. Make useful things. Educate your citizens. Don't let your neighbor down the street beat and abuse their family (citizens). Don't let them starve. But don't be an over-zealous, nosey bully with a secret greedy agenda when you intervene. Volunteer to go in on big projects that make the whole neighborhood better, safer and more advanced.
