The purpose of HS2 is not to ‘shave 20 minutes off a train journey’. It’s not even primarily intended as an upgrade to outdated and creaking infrastructure. The revolutionary thing it does is take high speed trains off standard routes. Why is this important? 1/

If you run mixed speed trains on the same lines, you have to run fewer trains. Trains can’t move out of each other’s way or overtake, so for every fast train you have to remove a couple of slower trains so that the fast train doesn’t catch them up. 2/

HS2 takes the fast trains and puts them on a separate line. That means you can run more fast trains AND more slow trains. It’s estimated that this will translate into about a 1% initial transfer from road to train. That doesn’t sound like much, but that’s 1/100 car journeys. 3/

That’s tens of thousands of trips per week taken on the train instead of by car - safer, more environmentally friendly trips. And that’s without any other programmes to incentivise train journeys or discourage car journeys. 4/

It also increases capacity for commercial freight - freight that otherwise would go by plane or road, both much more polluting/high carbon options. 5/

You can’t currently change these high carbon and high pollution behaviours because there isn’t a good alternative - if the train can’t be relied upon to get you there on time, why wouldn’t you drive? 6/

Seeing environmentalists campaign AGAINST HS2 after decades of banging the drum *for* public transport is baffling. Like this is literally what we wanted? More train capacity, fewer car journeys and fewer flights, fewer new roads and airport expansion? /fin