It's more about the political economy where funneling through certain well connected companies generate a lot of goodwill among the middlemen who then funds pac's and pay for advertisements then it's about a direct relationship between the senate and the employment status of their workers.
Is it a senate cultural thing that they all tell themselves despite tenuous links to reality?
Is it kickbacks?
Why doesn't the logic apply to infrastructure projects which seem more marketable?
The way it works is, the politicians who got the plant created out there earned some cachet with voters, and politicians today would get crucified by voters and the unions if they tried to move the plant. It's important enough that presidents give speeches there. (to put that fully into context: there is absolutely no other reason for politicians to give speeches there or even to be there, except perhaps some obscure form of self-flagellation) And of course voters in the entire surrounding state are pretty sensitive to the notion of losing industrial jobs, which earns the plant some protection from the state's US senators as well. People on the other side of the state might not be talking about it today, but they'd be talking about the plant if it got closed. Politicians understand this.
You never see a senator take credit for a plant opening/expanding on their re-election blurb/townhall? You must be in an incredibly safe state.
> Why doesn't the logic apply to infrastructure projects which seem more marketable?
It applies to them, too. Again, if you're not seeing this, either your senator isn't doing much of it, you're not paying much attention to their campaign, or they are in such an incredibly safe district that their only challenger is Bozo the Clown.
