As the US marks its 250th birthday, it operates an empire in all but name

There will be parades and speeches, fireworks and barbecues, and a healthy dose of patriotism. This Fourth of July, Americans celebrate the 250th anniversary of their country’s independence from the British empire. Many remain unaware of when their continental republic became an empire of its own. Neither will many of them know that at the turn of the 20th century, the founding principle of the De