"President James K. Polk, who presided over the invasion of Mexico, saw its significance as an example of how a democracy could carry on and win a foreign war with as much "vigor" as authoritarian governments were able to do. He believed that an elected civilian government with its volunteer people's army was even more effective than European monarchies in the quest for empire. The victory over Mexico proved to the European powers, he felt, that the United States was their equal. Standing tall through military victory over a weak country: it was not Ronald Reagan or George W. Bush who thought up that idea. The tradition is as old as the United States itself."