I first saw my London tank on Millennium Eve. I was casing a route to take a party of revellers on foot from Peckham to the river that evening. It went up the path of the old canal from Peckham Library through Burgess Park, over the Old Kent Road and on through Bermondsey Street. Cutting across the Old Kent, I turned into Mandela Way, and there it was, stood defiantly on a triangle of land where the Way met Pages Walk, nominally fenced off but clearly functioning as common ground.

A huge, toylike T-34, with the soft edge of its rounded turret, and its cannon rising dramatically westwards. I clambered onto it and posed, for nobody. Every boy's war game come to life, and tamed. Fenced in, and threatened only by nettles and buddleia. Like a great many toys in this world, it had been bought as a present, ostensibly at least, by a father for his son. Protest, though, was not far away. Russell Gray, who lives just around the corner, named his tank Stompie, after Stompie Muketsi Sepei, the teenager murdered by Winnie Mandela's thugs in 1989. The point being that even simple political gestures—like a local council naming a street for an anti-apartheid modern legend—can have muddied resonances.

The authorities, for their part, were interested in Stompie. For a while a 'remove for disposal' sticker adorned its green-grey sides. The spectre of planning permission was raised. Finally, the MoD wondered if it had been properly decommissioned, and suggested it might be a security risk. To date, Gray is yet to trundle it across Westminster Bridge towards Parliament, with insurrection on his mind. The closest it's come to toppling the state is bursting through the castle walls in the magnificent opening of the Ian McKellen film of 'Richard III', as part of its tank travels between Czechoslovakia and Bermondsey.

Today, though, the Mandela Way tank is pink. This was the work (sanctioned by Mr Gray) of cubitt artists, under the leadership of American artist Aleksandra Mir. Its transformation took place in July 2002, as an example of what Mir calls 'Summer Art'. 'It took 5 girls to paint it in the scorching sun.' she says, and you can find pictures of the posing tank girls online. Although Mir is coy about its inspiration (citing 'everything else that's pink in the world'), the reference to Prague's famous pink tank seems unavoidable.

This symbol of aesthetic-political subversion dates back to 1968, when Soviet tanks rolled into the Czech capital to crush the Prague Spring. They mounted one of their T-34s on a pedestal in the city's central square—supposedly as a memorial to the Russian soldiers who had liberated the population from the Nazis back in 1945, but in practice to remind the locals that Moscow didn't take kindly to anyone 'reforming' Communism. Local artists were less impressed, however, and painted it pink.

Most people know the monument from its second incarnation, created by artist David Cerny to celebrate the Velvet Revolution. He tried the trick again in 2001, with a new tank. Wary now of souring relations with Russia in the brave new post-Soviet Europe, the authorities resisted. The pink tank lives on in Prague only as a souvenir t-shirt. Here, we have Stompie.