Perhaps it is the sleek, silvery curves of its late Sixties design, but there is something curiously brazen about the Watergate complex. There it sits, this opulent nest of offices, apartments, and hotel rooms, preening on the east bank of the Potomac in the Foggy Bottom district of Washington DC – plush, proud and seemingly oblivious to its infamy.
Or maybe my own expectations are awry. I had anticipated an air of sackcloth and ashes to the most notorious address in the US capital – or, at least, a quiet willingness to blend into the background. But as I stroll around its interior courtyards, peering through doors and into reception areas, all I can detect is an affluent shrug, as if nothing happened here.
Of course, it is not these buildings' fault that they were the starting point for the most famous political downfall of the 20th century. When, on 17 June 1972 – 40 years ago today – five men were caught breaking into the Democratic National Committee headquarters at the heart of the compound, it triggered a series of events that would depose a president.
Four decades on, Richard Nixon – the commander-in-chief for whom these agents were ultimately working as he sought re-election – remains the only man to have resigned America's top job, the chain of evidence eventually revealing a campaign of dirty tricks that ran right to the Oval Office. And Watergate has become a byword for scandal, that "-gate" suffix being tagged to almost any shameful public affair.
But what is most immediately shocking about the Watergate complex is how close it lies to the seat of power. Walking east on G Street NW, it takes me just 15 minutes to cover the one mile and 10 blocks to the front of the White House. This small distance makes it clear: Nixon's murky deeds were done on his own doorstep.
And yet, it is this very frisson – this sense of a city always shifting through the gears of government, alive with intrigue – that makes Washington so compelling a place to visit.
It was, after all, supposed to be a political animal. When it was founded in 1791, only 15 years after the Declaration of Independence, the plan was to create an enclave entirely separate from the states of the union. So it remains, a nugget of pure bureaucracy, hard pressed to the north, south and east by Maryland, and by Virginia to the west. And many of the US's key moments have played out within its limits: Abraham Lincoln's battle to abolish slavery, and the assassination with which he paid for his triumph; the civil-rights marches of the 1960s; the protests against the Vietnam War in that same turbulent period.
In Fear and Loathing on the Campaign Trail '72, the irreverent tome with which he charted the same election process that was defiled by Watergate, Hunter S Thompson described a city in which "there is a fast-swelling undercurrent of political angst in the air". He was referring to anti-Nixon sentiment as the sprint for the White House gathered speed – but his words might equally refer to now, as the 2012 presidential race nears its endgame. When I stroll 15th Street NW, below Pennsylvania Avenue, images of the incumbent outnumber those of Justin Bieber at the souvenir stalls – as if in the hope that Barack Obama might be re-elected on T-shirt sales alone.
Those who want to immerse themselves in the gloopy soup of politics can certainly do so in the American capital over the coming months, as the 2012 presidential race nears its endgame. It spits its opinions from the pages of The Washington Post in the coffee shops of Dupont Circle and Georgetown. And it shouts its presence from the landmarks on the long strip of the National Mall: the elegant obelisk of the Washington Monument, built in tribute to the first US president between 1848 and 1884 – and still, at 555ft, the tallest structure in the city; the grand bulk of the Lincoln Memorial, where the statue of the 16th president has statesmanlike poise; the reflective walls of the Vietnam Veterans Memorial, where the presidential reign of Lyndon Johnson might be inscribed alongside the 58,272 names of the dead and missing.
Politics also infiltrates spaces where you might not expect it. The excellent National Air and Space Museum, part of the Smithsonian, does the raw optimism of America's 20th century, notably in the 1903 Wright Flyer – but also dispenses Cold War posturing in the potential Armageddon of a Pershing II long-range nuclear missile.
The National Portrait Gallery, meanwhile, tells the US tale through pieces such as Edward Hopper's Cape Cod Morning, but is most of interest for its collection of presidential portraits, each casting its subject in a different role: Kennedy as matinee idol, gazing softly at the viewer; Clinton as modern icon, face represented by a patchwork of cubes; Reagan as banker, grinning in Wall Street pinstripe; George W Bush as an unconvincing everyman; Nixon trying for "playful", arm on the back of his chair; Lincoln as thinker, hand on chin.
Lincoln has another moment, nearby at Ford's Theatre, the site of his fatal encounter with a bullet on 14 April 1865. It would be easy to dismiss this dark mark on the timeline as a schlocky house of horror, but the theatre is aware of its significance, staging provocative productions and preserving Lincoln's box as he left it, Stars and Stripes hanging forlornly over its lip. The pistol fired by John Wilkes Booth is on show in a glass case downstairs.
The spectre of presidential death haunts Washington. It is there in the secret service officials who lurk, itchy of trigger, around the White House grounds. And it is there when I cross into the state of Virginia via the Arlington Memorial Bridge (below planes coming in to land at Ronald Reagan National Airport – a hat-tip to a man who survived his own date with an assassin in 1981). On the far side, John F Kennedy lies amid America's military fallen in Arlington National Cemetery.
His grave enjoys pride of place, pinned to the gentle curve of its own small hillock, kept warm by an "eternal flame". The location of this quasi-shrine is entirely deliberate, "affording" JFK an uninterrupted view across the river to the Lincoln Memorial, the Washington Monument and the US Capitol. There is something almost unsettling about this elevation; another hint that it is hard to evade the pull of politics in this city of spin.
However, I make one attempt to do so, catching the subway up to U Street, a traditionally black area of a city whose large African-American population is a legacy of its time as a haven in the fight for emancipation. Here are lively bars and restaurants – and a further nod to the ballot box. Midway along the avenue, Ben's Chili Bowl hit the jackpot in 2009 when the newly elected Obama popped in to dine on $3 hot dogs and display the common touch. A wall plaque and photos denote the table where he ate. Quite what the slyly aloof Nixon would have made of a president sullying his hands with ketchup can surely be guessed. Lincoln, you suspect, may have smiled in approval.
Under the skin of Watergate
Washington is renowned for the stately museums of the Smithsonian Institution. But three less-known city landmarks examine some of the fields that came together amid the murky waters of Watergate.
Richard Nixon's downfall was largely driven by the media – notably journalists Carl Bernstein and Bob Woodward of The Washington Post. So it is appropriate that Washington can boast the Newseum (001 888 639 7386; newseum.org) – which tries to underline "the value of a free press in a free society". Presciently, the News History Gallery features the stairwell door from the Watergate complex whose tampered latch was spotted by security guard Frank Wills, beginning the whole process.
The seamiest side of the Watergate affair was surely the administration-approved use of covert tactics. E Howard Hunt Jr, one of the Nixon-affiliated operatives who concocted the plan to break in to Democratic National Committee headquarters and wire-tap selected phones, was an ex-CIA agent. These dark undercurrents come into focus at the International Spy Museum (001 202 393 7798; spymuseum.org), which looks at how espionage became the frontline of warfare in the 20th century.
Similarly, the rise of the FBI – Woodward and Bernstein's anonymous source, Deep Throat, was eventually revealed as Mark Felt, the FBI's associate director – is part of the tapestry on show at the Crime Museum (001 202 393 1099; crimemuseum.org). Here, workshops explain the importance of forensics in detective work.
Hotel Monaco, 700 F Street NW (001 202 628 7177; monaco-dc.com). Doubles from $285 (£180), room only.
American Art Museum and National Portrait Gallery, F Street and 8th Street NW (001 202 633 1000; npg.si.edu). Admission free. Arlington National Cemetery, Memorial Drive, Virginia (001 877 907 8585; arlingtoncemetery.mil). Admission free.
Ford's Theatre, 511 10th Street NW (001 202 347 4833; fords.org). Theatre tours free. National Air and Space Museum, 6th Street SW and Independence Avenue (001 202 633 1000; airandspace.si.edu). Entry free.
Eating and drinking there
Ben's Chili Bowl, 1213 U Street NW (001 202 667 0909; benschilibowl.com)