Fifty heavy lifters

Washington changes whenever the White House gains a new occupant. When that involves a 47-year-old African-American from Chicago replacing a 62-year-old white Texan, the effect is likely to seem unusually pronounced.

Perhaps the most visible alterations will be in the lower average age of the Barack Obama people, the greater ethnic and gender diversity of the new president’s administration and the fact that it is made up of a more metropolitan and technologically savvy crowd than those they replace.

In spite of Mr Obama’s grassroots campaign rhetoric, in a presidential system the most important change starts at the top and cascades downwards. In contrast to George W. Bush, who was usually in bed by 10pm and rarely accepted invitations to dinner outside the White House, Mr Obama is a regular night bird. His staffers will have to get used to a diet of evening meetings as well as the usual murderously early morning start.

In addition, Mr Obama has hinted that Sunday might be a working day. Unlike Mr Bush, who had six weekly intelligence briefings a week, so far Mr Obama has been receiving seven.

Before the first month is out, White House staff are likely to be about as well acquainted with the presidential secret service contingent as with their own families. Indeed, so much time are staffers expected to spend at the White House that Obama officials are exploring ways in which their families can regularly visit them.

More broadly, power in Washington will switch from conservative to liberal and from late middle-aged to young middle-aged. Many of the 3,300 presidential appointees are in their twenties or thirties and are products of America’s Ivy League universities.

Unlike much of the Bush crowd, which had a heavily southern tilt, many will be from either America’s east or west coast – the much derided “bicoastal” set of liberal elitists.

The same may apply to the hundreds of students or young postgraduates filling the coveted internships across the administration. Under Mr Bush, a large share of interns were fervent Christians from the Regent or Liberty universities in Virginia, in spite of those institutions’ less than top-flight academic reputations.

In short, the Obama bunch will seem more meritocratic, workaholic, thrusting and possibly self-righteous than those they replace. Expect the bars to be slightly busier and the pews a little more thinly populated.

But commentators sometimes also overstate the social effects of a change of administration. In practice, Washington has always been – and is likely to remain – an incestuous town of “Beltway insiders” who share an addiction to politics and government.

Many of the incoming crowd, from Mr Obama downwards (including Hillary Clinton, Eric Holder and much of the rest of the cabinet) were living in Washington beforehand. Most of the outgoing Bush brigade are, moreover, unlikely to be leaving town in a hurry. America’s capital presents many tempting think tank sinecures and lobby group partnerships. Not for nothing is it called the revolving door.

As for social life, the long working hours will usually win out. As Harry S. Truman once said: “If you want a friend in Washington, get a dog.”

Overview and profiles by Edward Luce, Daniel Dombey, Krishna Guha, Demetri Sevastopulo and Andrew Ward