If you want a friend in Washington,” Harry Truman said, “get a dog.” He was commenting on what a brutal, backbiting, primordial swamp the capital is. But the sentence could just as well be taken to mean: you won't make friends if you don't have a dog.

It should come as no surprise that in his acceptance speech Barack Obama told his daughters Malia, 10, and Sasha, 7: “I love you both more than you can imagine. And you have earned the new puppy that's coming with us.”

This was not just a sweet gesture to his daughters: it was a statement of intent. He may have won a landslide with a message of change, but he needed to reassure voters that one of the White House traditions that they hold most dear, whether the occupant is a Republican or a Democrat, would be upheld. More than half of America's 43 presidents have owned dogs and in recent years a canine friend has meant more than just a way of softening a Commander-in-Chief's image. It has become an essential job requirement.

We may love our pets in Britain but they rarely play much of a role in politics. Humphrey the Downing Street cat entered the nation's consciousness only when John Major lost him and again when Cherie Blair had to deny reports that he was removed from No 10 because she disliked the animal. It is hard to imagine any other country in which a newly elected leader would announce as his first executive decision the appointment of a First Pooch. White House dogs are involved in diplomacy, political crisis management, even in helping to hold their owners' precarious marriages together. Then they write books.

'Change has come' - Obama wins in landslide

Sweeping victory for America's first black president is greeted by tumultuous scenes Watch our video

• Analysis: Barack Obama's victory is head-spinning stuff

• Full video and text: Barack Obama's victory speech

• Early US Election exit polls give hope to Barack Obama

Michelle Obama: a new type of First Lady

For Carla Bruni the game is finally up. In Michelle Obama she has truly met her match - a First Lady like none before

BACKGROUND

• Bush - 'We should all be proud of Obama'

• The challenge that greets Obama

• Full video and text: Obama's victory speech

• Voters honour Martin Luther King's dream

Multimedia

• Team Obama - who are they?

• Bonjour 'Barack'

Multimedia

• Pictures: All the presidents' dogs

Multimedia

• Blog: Obama - which puppy should he buy?

George Washington found time between winning the Revolutionary War and founding the nation to own ten hounds: Taster, Cloe, Tipler, Forester, Captain, Lady Rover, Vulcan, Sweetlips, Madame Moose and Searcher. Theodore Roosevelt, who worked hard on his macho image, kept a pitbull, Pete, that nearly provoked a diplomatic incident when it attacked the French Ambassador, tearing the seat out of his trousers. Pete was banished to Roosevelt's home on Long Island. His removal, however, did not leave Roosevelt lonely. The President liked keeping animals almost as much as he enjoyed killing them and brought a menagerie to the White House that included a bear, a badger, a macaw, a lizard, a hyena, snakes, guinea-pigs, a hen, a rooster with one leg, a rabbit, three ponies and a barn owl.

Subsequent presidents returned the focus to less exotic, four-pawed pets. Franklin D. Roosevelt's Scottie, called Fala, became so much part of his avuncular image that it received sacks of fanmail, was buried alongside his master and is immortalised in the memorial to FDR on the National Mall. Roosevelt responded to a false story that Fala had been left behind on a trip to the Aleutian Islands and a destroyer had been sent to pick him up, with a speech in which he said: “His Scotch soul was furious. He has not been the same dog since. I am accustomed to hearing malicious falsehoods about myself...But I think I have a right to resent, to object to, libellous statements about my dog.” Fala supposedly bonded with Rufus, Winston Churchill's poodle, in the secret confines of a cruiser off Newfoundland in 1941.

The Cold War was thawed by a degree or two when Nikita Khrushchev gave Pushinka, a mongrel descended from Russian dogs sent into space, to President Kennedy's daughter, Caroline. A litter of puppies was born in the White House. The family's other dogs included Charlie, a Welsh terrier.

Lyndon Johnson caused uproar when he was pictured picking up his beagles, Him and Her, by their ears. Richard Nixon proved master of using his cocker spaniel, Checkers, to get out of trouble. When he was Eisenhower's vice-president he was accused of pocketing money from supporters and for accepting the dog as a gift. He went on television to deny the accusations, held up a picture of the dog, said his kids loved the animal and “regardless of what they say about it, we're gonna keep it”. Viewers lapped it up and the crisis was defused.

His successor, Gerald Ford, had a more practical use for Liberty, his golden retriever, whistling for her to come and break up boring meetings.

The Bush political dynasty is matched by that of their dogs. George Bush Sr had an English springer spaniel, Millie. Millie's Book: As Dictated to Barbara Bush, described a day in the life of the President, which burnished his profile and cemented his wife's status as the nation's grandmother. Spot, one of Millie's puppies born in the White House, returned with George W. and died there in 2004. The outgoing President now has two Scottish terriers, Barney and Miss Beasley. However low his opinion poll ratings, the dogs are always ready to come bounding enthusiastically across the lawn to greet him.

His predecessor relied even more heavily on a dog pal in times of trouble. The Clintons arrived at the White House with their cat Sox and later Clinton was given Buddy, a labrador. Dear Sox, Dear Buddy, a collection of letters sent to the pets sold well, but the two didn't get along. Like most things about the Clintons, their cat attracted controversy. The Clintons had her declawed to save the antique furniture, provoking uproar among animal welfare groups. Then when they left office it was announced that it was off to live with Bill's secretary, Betty Currie, prompting unfair accusations that Hillary didn't care for the moggie and had just used it to soften her own image (this was a little unfair given that Sox had been the family pet back in Arkansas).

Buddy was a faithful and helpful presence to his master. During the Monica Lewinsky scandal it appeared to be the only member of Bill's family that was pleased to see the President. Perhaps this is too cynical, but it was a useful image for Clinton to be seen serving his time in the doghouse with the dog, before his spouse forgave him. After he left office Buddy was accidentally killed near the family home in Chappaqua, New York, when a vehicle ran over it. Bill was said to be heartbroken.

One thing Obama will need to watch out for is competition for the job of top dog. Dick Cheney once dressed his labradors, Jackson and Dave, as Darth Vader and Superman for a Hallowe'en party but, like their owner, they mostly stayed in the shadows.

Joe Biden, however, has said that his wife had promised him a “big dog” if he got elected. Not too big, Mr Vice President-elect.

Expect to hear a great deal more about the First Dog, probably rather more than you will about the two girls for whom it is bought. Then one day there will be a section devoted to it in the Presidential Pet Museum. Yes, of course there's a Presidential Pet Museum. Where else would you find a portrait of Lucky, President Reagan's Bouvier des Flandres, made from its own hair?

A dog isn't just for one term, Mr Obama, it's for life

As leader of the world superpower, choosing a dog probably does not rate alongside forging relations in the Middle East or reducing America's national debt, yet the breed of the Obamas' new canine companion could be more of a headache for the President-elect than he realises. Larger dogs may be more child-friendly but they often have a shorter lifespan and cost more to feed than smaller ones, which must be a consideration in economically blighted times. While a Jack Russell might be lively, it is also more likely to bite than any other breed. This could become diplomatically explosive should the Iranian Ambassador's attempt to pat the President's pooch be misinterpreted by the mutt as an act of war.

And then there are allergies. For the Obamas, whose daughter Malia suffers from them, a breed with a short, predictable coat is crucial. Yet, hypoallergenic dogs, such as the American hairless terrier, are not the best-looking of breeds when it comes to those “impromptu” fur-frolicking photo calls.

Lastly, there is the important issue of what your dog says about you. According to Beverley Cuddy, editor of Dogs Today, psychologists have found an inverse correlation between a man's masculinity and the size of his dog. A man who chooses a very large canine, such as a Great Dane, could signal a lack of confidence. This does not bode well for Jo Biden, who has already announced that he is going to choose a large breed.

Surprisingly, the American Kennel Club has already polled its members on which breed should be the next White House dog basket incumbent and, after 42,000 votes, the poodle beat the soft-coated wheaten terrier by a dog's hair's breadth. Here at The Times, however, we have a few suggestions of our own:

THE RODINGLEA SCRUFFY
The brightest dog in town. A blend of bearded collie, border collie and English springer spaniel, this dog has been bred to be a canine genius and is so evolved that it can even speak 15 recognisable words. It could hold its own press conferences and even market its own top-selling books.
Downside: danger of indiscretion and becoming a double agent in return for sausages.

THE LABRADOR
A favourite of British MPs and No1 dog in Britain. Docile, biddable, needs little grooming and would do wonders for the Special Relationship.
Downside: a gun dog (how neocon!) that needs a lot of walking and could run to fat on too many banquet titbits.

THE AUSTRALIAN SHEPHERD DOG
A native to America and would be a novel breed for the White House. As a dog with a working past, it could be useful for herding the press corps. It is also loyal and protective.
Downside: its name could be construed as unAmerican.

THE PUGGLE
A cross of the pug and the beagle. It looks like the pug of Hogarth pictures, is flat-coated and much favoured by the rich and famous. It can strut its stuff, so would cope with the cameras and, as it is blessed with the gentle nature of the beagle, would make a perfect presidential companion.
Downside: could demand more attention than strictly needed.

THE RESCUE DOG
Would show that Obama is in touch with the people and that, just as anyone can become President, any canine can become First Dog. Could make rescue dogs fashionable.
Downside: not knowing a dog's history can mean more work and having to have faith and trust in the future.

Alexandra Blair

Money Central: the world's ten most pampered pets

Times Recommends

• Thousands of Tamils dying in 'welfare camp'
• Jackson 'rebuilt his nose before he died'
• Renewed Iran protests crushed by militia