Carl Bernstein (of Woodward and Bernstein fame), rightly says that Bush has done more damage than Nixon:

"In the case George W. Bush, the American system has obviously failed -- tragically -- about which we can talk more in a minute. But imagine the difference in our worldview today, had the institutions -- particularly of government -- done their job to ensure that a mendacious and dangerous president (as has since been proven many times over, beyond mere assertion) be restrained in a war that has killed thousands of American soldiers, brought turmoil to the lives of millions, and constrained the goodwill towards the United States in much of the world."

...

"In the current administration we have seen from the President down -- especially Vice President Cheney, Attorney General Gonzales, Condoleeza Rice, Donald Rumsfeld -- a willingness to ignore the great constitutional history of the United States -- to suspend, really, many of the constitutional guarantees that have made us a nation apart, with real freedoms unknown elsewhere, unrestricted by short-term political objectives of our leaders.

"Then there are the Geneva conventions: Who would have dreamed that, in our lifetime, our leaders would permit their flagrant abuse, would authorize torture, 'renditions' to foreign-torture chambers, suspension of habeus corpus, illegal surveillance of our own citizens....

"But perhaps worst, has been the lying and mendacity of the president and his men and women--in the reasons they cited for going to war, their conduct of the war, their attempts to smear their political opponents.

"Nixon and his men lied and abused the constitution to horrible effect, but they were stopped.

"The Bush Administration -- especially its top officials named above and others familiar to most Americans -- was not stopped, and has done far greater damage. As a (Republican) bumper-sticker of the day proclaimed, 'Nobody died at Watergate.' If only we could say that about the era of George W. Bush, and that our elected representatives in Congress and our judiciary had been courageous enough to do their duty and hold the President and his aides accountable."