In Crystal Palace park grandiose steps and monuments currently lead to an empty space. This patch of grass was the second location of the palace, re-erected in suburban Sydenham in 1854, its prefabricated iron and glass modules rearranged from the original in Hyde Park.

The Crystal Palace, designed by Joseph Paxton in 1851, was intended as an immense symbol of the modernity and technological scope of the British empire, its glazed transepts filled with a Great Exhibition of the Works of Industry of All Nations, where the products of advanced technology – daguerreotypes, displays of steel-making – sat alongside displays of imperial plunder. There's a certain historical symmetry that the proposal to build a replica of the palace comes from the Shanghai-based developer ZhongRong Holdings; and not only as a form of lucrative post-imperial revenge, in an era when Chinese buy-to-let investors are directly appealed to by the likes of Newham council.

Chinese cities have recently become notorious for their sheer degree of copying and reproduction, with hundreds of replicas of famous historic buildings and even of recent ones – such as the copy of Zaha Hadid's Guangzhou Opera House, under construction almost immediately after the original was completed. But in London, the Crystal Palace replica is only the most vast – and probably the least likely – of a smaller but still significant series of proposed reconstructions. This says something increasingly unnerving about the city.

The founders of architectural preservation loathed the palace – the combination of skill-free mechanical labour in erecting its prefabricated parts and the machine-made ornamental tapestries and knick-knacks on display so alarmed architectural opinion that it probably helped spark the Arts and Crafts movement, with its often socialistic, workerist conception of expressive craftsmanship. Early preservationists such as John Ruskin and William Morris also hated reconstruction, which they considered fakery, but that won't stop their successors from supporting a replica palace.

It may share a future tourist itinerary with the Euston Arch, where the perfectly decent 1960s terminus building will be replaced with a retail hangar fronted by a reconstructed Doric propylaeum. The campaign to rebuild the arch, demolished in 1962 – needlessly and callously – has even managed to fish out of the River Lea a few fragments of the original ashlar. Then, perhaps, the tourist will be able to travel south of the river to a reconstructed Skylon, the steel tower erected as part of the 1851 Great Exhibition's self-conscious successor, the 1951 Festival of Britain and demolished as "three-dimensional socialist propaganda" by Sir Winston Churchill less than a year later.

What do the Crystal Palace, the Euston Arch and the Skylon have in common? They all share a certain combination of modernity and imperialism – the longing for a "workshop of the world" in a country dominated by a wilfully unproductive rentier capitalism. The spirit of empire on the right; the spirit of 1945 on the left, both hark back towards a previous era of optimism, production and nationalism, something that, in the case of the right, by no means precludes selling off any given public space or public utility to any given investor.

It's the urban equivalent of the freakish Keep Calm and Carry On cult, that never actually produced wartime poster that has become probably the best emblem for the dissembling pageantry and PR of 21st century austerity; a fitting stage for the currently incessant royal pageantry and empty-headed commemoration and an appropriate faux-historic series of locations for Michael Gove's jingo history classes. All three reconstructions involve willing a return of an urban, industrial era of great entrepreneurs and industrialists, in a country dominated by rent-seeking and suburbanism, as if they can rebuild it back into existence. The likely outcome will be a Virgin Trains ashlar arch, a futurist tower in front of Costa and Wagamama, an iron and glass palace owned by a Shanghai billionaire.

What will it have to do with the actual empty public space in south London that it will be filling? It will, chances are, enclose a chunk of park and turn it into a private, paying attraction. It will represent an era that preferred post-imperial melancholia to the much greater challenge of imagining what building for today's London, and today's Londoners, might look like.