It is not a joke. Do not dismiss it without giving it some thought.
The argument goes something like this; Bush has achieved something remarkable through negation. He has united people of different ideologies into a consensus of what not to do. Everything he has done, especially in foreign policy, will be studied in seminars and history books as Exhibit A of what must be avoided at all cost, "never again". Bush presidency will be a cautionary tale, like the decline of the Roman Empire, warning generations to come what can happen to an Empire, how a foolish Caesar can weaken the empire by launching ruinous wars that sap its treasury, ruin its reputation.
http://www.nybooks.com/...
"One of the few foreign policy achievements of the Bush administration has been the creation of a near consensus among those who study international affairs, a shared view that stretches, however improbably, from Noam Chomsky to Brent Scowcroft, from the antiwar protesters on the streets of San Francisco to the well-upholstered office of former secretary of state James Baker. This new consensus holds that the 2003 invasion of Iraq was a calamity, that the presidency of George W. Bush has reduced America's standing in the world and made the United States less, not more, secure, leaving its enemies emboldened and its friends alienated. Paid-up members of the nation's foreign policy establishment, those who have held some of the most senior offices in the land, speak in a language once confined to the T-shirts of placard-wielding demonstrators. They rail against deception and dishonesty, imperialism and corruption. The only dispute between them is over the size and depth of the hole into which Bush has led the country he pledged to serve."