The US president is now as powerful as a monarch, according to a new book by an American professor published to coincide with the start of George W Bush's second term.
By Richard Greene
Even powerful mid-century presidents such as Franklin Delano Roosevelt recognised checks on their authority, says Stephen Graubard, who is old enough to have attended Roosevelt's last inauguration in 1945.
But since Ronald Reagan, the powers of a president and his "courtiers" have become increasingly untrammelled, Professor Graubard told BBC News.
"He is not totally unchecked but his power is immense," he says of recent presidents, several of whose closest advisers - including Donald Rumsfeld, Henry Kissinger, McGeorge Bundy and Zbigniew Brzezinski - he has known personally.
"FDR worried all the time about other authorities who might try to inhibit his plans. This man [George Bush] knows nobody is going to check him.
Bush is not the only president Graubard criticises
"He has been made ridiculous by certain films, but does Bush really give a damn what the New York Times thinks of him? Roosevelt did.
"A king claims certain prerogatives. He is under the law but he has immense discretion in what he can do, especially in foreign affairs."
The age of Reagan
The great early-20th-Century writer Henry James may have dubbed Theodore Roosevelt "Theodore Rex", but meant it as a joke, the author says.
In his book, The Presidents: The Transformation of the American Presidency from Theodore Roosevelt to George W Bush, he divides the 20th Century presidency into three eras.
Today's patriotism is a legacy of the 40th president, Graubard says
The White House became extremely powerful under such towering figures as the two Roosevelts - Theodore and his cousin Franklin - Woodrow Wilson, and Harry Truman, he says.
It was much weakened in the 1960s and 1970s but starting in 1980, Reagan restored to the institution all its previous grandeur and more again, the historian argues.
"We are living in the age of Reagan," he says, adding that George W Bush - who begins his second terrm on Thursday - governs very much in the mould of the 40th president.
Mr Bush's displays of patriotism echo Reagan's, he says. And he accuses both of a tendency to inflate the dangers the United States faces.
"That we have never lived in such dangerous times is - to use a four-letter word - crud," he says, referring to Mr Bush's claims about the scale of the threat posed by terrorism.
"When you stop and think of our situation in 1942 - those were dangerous times," he says.
But if Professor Graubard is critical of the current President Bush, he is hardly more complimentary about other recent presidents, Republican or Democrat.
Graubard has known several top advisers to presidents personally
He describes George HW Bush as a stiff patrician who tried and failed to imitate Reagan's style, and says Bill Clinton's over-arching concern was with self-preservation.
He dismisses Jimmy Carter as "the one real non-entity in the book".
Even the highly-regarded John F Kennedy "didn't have great domestic or foreign policy achievements", he says, while Lyndon Johnson may have been "the greatest domestic reformer of the century", but was a failure in foreign policy.
And although Richard Nixon came to the White House knowing more about the job than any previous incoming president, Professor Graubard says, "he was a terrible human being".
Stephen R Graubard, now retired, has been assistant professor of history at Harvard and professor of history at Brown University. The Presidents is published by Allen Lane in the UK and by Basic Books in the US, where its title is Command of Office.
This administration has eroded all checks and balances to the point where it seems like the president can do what ever he wants with no consequences. There seems to be no accountability. These are sad days.
Brian Bednarek, Woodbridge, NJ, USA
Pure idiocy that's written to entertain the anaemic chattering classes of Europe and the developing world, who'd like nothing more to subjugate the United States to a version of "human rights" that they themselves pay only lip service to. To say that Bush isn't checked is simply erroneous: the successful blocking of his high-profile judge appointments just one powerful example. Furthermore, Bush's budgetary spending spree demonstrates that he doesn't exactly consider himself in the position to make too many enemies. King's don't worry so much about enemies because they can eliminate them.
Matt, New Haven, CT
The checks and balances have absolutely eroded over the last 15 years and it is moving at light speed during this present Administration. I believe the increasing number of conservative media outlets and an unchallenging and apathetic public are the main reasons for this.
Rod Rodman, Reno, NV USA
I intend to read the book - it's long overdue. Those who believe the President's power should be absolute know nothing about history. The unique strength of this nation has been derived from separation of powers.
Pat Young, Mt. Vernon, WA, USA
I am a Brit who has recently moved to the US and also recently read 'I Claudius' by Robert Graves. I found grim similarities there between the collapse of democracy in Rome and what's happening in the US. Though I have not read his book yet, Prof. Graubard's observations seem right on the money to me.
Alex Lamb, Santa Cruz, CA, USA
No doubt many of the criticisms are valid. But the job of a leader is to lead. Bush is leading. It's a tougher job than writing books.
John Doyle, Dublin, California, USA
The checks and balances of our government are eroding due to an increasingly apathetic public with a very short attention span. This has led the US to economic imperialism.
Tad Peterson, Murfreesboro, USA
The book is marvellous and I especially praise the brutal honesty with which Prof. Graubard has spoken about the presidents of the USA. Recommended for everyone who is interested in the American domestic and foreign policies, and especially for those who wish to see how the politicians work more for self-preservation than for the general wealth of the people.
Keshav Sharma, USA
This country needs a very strong leader. I am all in favour of more presidential power. The United States is an Empire in mind and spirit. Perhaps it should be in body as well.
David Easley, Memphis, USA
David Easley's comments are a little worrying and go against the ideals of America's founders. Rome fell as an empire, not as a republic and the founding fathers of the United States specifically did not want the possibility of a Roman style empire arising out of their Roman inspired republic!
James Gibbins, Melbourne, Australia
It's interesting that the good Professor advises that President Carter is "the one real non-entity in the book". President Carter took the decisive action of boycotting the 1980 Olympics in protest of the Soviet invasion of Afghanistan. President Reagan sounded more aggressive, but never took an overt action, of that significance, against the Soviets. President Carter was also the first US President who took substantial action on human rights, while Reagan gave only lip service to that issue. So how can he be called a non-entity?
Jim Hopewell, Maryland, USA
Very interesting and worthwhile, a needed Presidential analysis.
Jeff S. Smith, Mt. Pleasant, Tx, USA
I have read Prof Graubard's book. It is an excellent and insightful analysis of American politics over the last 100 years.
Other historians may not have the courage to be so brutally honest, since they are not retired and may fear for their jobs or popularity.
Frank Wolstencroft, New York