How Hitler achieved absolute power

"Hitler took advantage of the situation to declare a state of emergency and encouraged aging president Paul von Hindenburg to sign the Reichstag Fire Decree, abolishing most of the human rights provisions of the 1919 Weimar Republic constitution." -- Article

Is there a difference in what the U.S. is doing to get the same powers?

"Those who do not learn from history are doomed to repeat it." -- George Santayana