The phrase 'water charges' still sends shivers up the spines of many residents in Leinster House.
Before Brexit and Trump, we used to get very excited - and rowdy - when we were debating how clean water would be funded.
It was a more innocent time but many TDs, and indeed now former TDs, still carry the scars.
On paper, charging households for water seemed like a reasonable ask. It might fall from the sky but it costs a lot to get it to our taps through an outdated Victorian system of pipes. Fine Gael and the Labour Party assumed the public would buy into the environmental argument that we all need to conserve such a precious natural resource.
But their timing was awful and then their implementation plan was even worse.
Amid furious austerity it was the final straw that brought normal people onto the streets in protest.
Hardliners took matters into their own hands and tried, with some success, to block the installation of water meters.
In his new book, 'In Deep Water', Michael Brennan writes that gardaí "had never seen anything like the water protests before".
At some stand-offs, gardaí were called 'Black and Tans'. And then there was the Jobstown incident.
The whole episode was put to bed when Fine Gael and Fianna Fáil combined after the 2016 election to take it off the political agenda.
The main parties could no longer afford to lose so much airtime to left-wing rivals like the Anti-Austerity Alliance and People Before Profit.
Those parties of protests won the battle - but in many ways they don't want the war to be over.
A politician without a cause can become irrelevant very quickly.
They have long suspected that the compromise on 'excessive water charges' was a back door to reintroducing domestic bills in the future.
Taoiseach Leo Varadkar has now effectively confirmed that, although he says this is unlikely to happen for a very long time.
He remains consistent in his view that people should pay for water, noting that at some point the EU may well force us to. However, the very fact Mr Varadkar has dared to re-enter the water debate will terrify many within his party.
Water charges are not a vote winner, even if there is a so-called 'green wave' under way.
It's interesting that it comes at a time when the world is gripped by a debate over climate action and the damage humans have done to the environment.
In next month's Budget, Finance Minister Paschal Donohoe will hike the carbon tax in a move that will be controversial but ultimately accepted.
The parents of the thousands of striking schoolchildren won't be publicly objecting, even if they privately don't want to pay more for petrol and diesel.
But water charges will forever be toxic.
It seems we'll pay so that we can pollute - but we expect the State to provide us with clean water for free.