Who knew we could feel this way about a building? It has taken the burning of history and the terrible toppling of the spire to remind millions in France and beyond of how much buried emotion was quietly invested in Notre Dame. When something has always been part of the skyline, when you pass it every day on the way to work, it’s easy to take it for granted. Landmarks are landmarks precisely because it’s so hard to imagine they would ever not be there.

In London, something similar is true of the Houses of Parliament, and there will have been shudders down a few spines on Monday night at the thought of how easily something equally catastrophic could have happened here. It’s not just the scaffolding that has been propping up Big Ben for months, or the water leaking through the ceiling that recently meant debate had to be suspended (and yes, the metaphors pretty much write themselves). Anyone who has ever walked through the “below stairs” bits of parliament during recess, one of the best chances its maintenance crews have to pull up floorboards and get at the vast tangles of antiquated cables beneath, will have an idea of what the building’s custodians are up against.

A building that in parts is as old as Notre Dame, which has had to be retro-fitted again and again over the years to catch up with such newfangled innovations as electric light, and which is now more than overdue a major overhaul if it is to remain a safe place to visit. When the Commons public accounts committee warned in its recent report on restoring our own national monument that “the risk of a catastrophic failure is high and growing with every month that passes”, fire was only one of the five most likely causes of disaster it identified.

Big Ben shrouded in scaffolding. ‘There will have been shudders down a few spines on Monday night at the thought of how easily something equally catastrophic could have happened here.’ Photograph: Tolga Akmen/AFP/Getty Images

But it sounds spoiled and elitist to demand billions for saving a historic building at a time when people don’t have roofs over their heads. So for years, parliamentary authorities have had to restrict themselves to patching up the bits that were most obviously falling down and occasionally pleading for a more urgent decision to be taken about all the other mounting threats. After much nervous hesitation – it’s seven years now since a study ordered by the House of Commons commission concluded that without a significant conservation effort, major and irreversible damage could be done – MPs accepted last year that moving out to allow for restoration was the only realistic option. But every plan for doing so is vulnerable to public outrage given the expense. Everyone understands the risks, when populists of all shades are whipping up resentment against politicians, of handing them yet another grievance to exploit. Now is arguably not the time. But the trouble is it’s never the time, until it’s too late.

What makes the Notre Dame disaster so compelling isn’t necessarily the fabric of the structure itself – although buildings are living history, places we can tangibly connect with all those who have worn grooves in the stone floors before us – but what it represents in people’s minds, both as a seat of religious faith and as part of a national story. The sight of its charred remains, at a time when France is in some turmoil and the forces of darkness seem to be rising across Europe, feels horribly symbolic; like a bombed-out relic of a war that has yet to happen. The emotional resonance of something catastrophic happening to the Palace of Westminster, in an era when Britain’s centuries-old democratic institutions have never seemed more fragile, shouldn’t be underestimated. We should treat this fire as the early warning it is.

• Gaby Hinsliff is a Guardian columnist