Importantly, even once built, it selects the wrong targets, not terrorists or military bases - but regular people who will be faced with scarcity of water and food, as the crops use Indus water. This would be something highly unethical, and also not something sustainable - once visuals of hunger start reaching screens across the world, the force to restart the supply would be strong.
Even if it were to translate to sanctions, I'm not so sure BJP wouldn't welcome it. "The Fatherland is besieged, let's unite together around Dear Leader and fight back like one" tends to be a very popular take in authoritarian countries for a reason, and it's that much easier to pull off when you can actually point at some way in which your country is targeted.
As far as US, under Trump, I'd actually expect it to back Modi.
Attacking Pakistan over this also strengthens BJP’s hand and distracts everyone from the complaints that have been eroding their support, like ongoing corruption, high taxes with lower quality of life, etc. etc.
Don’t expect the gulf countries to come to Pakistan’s aid over this, especially if it comes to money. Muslim countries in general like to pretend to be friends, and they certainly talk a big game.
When it comes to actually doing anything though, they just use anything going on as a chance to stab each other in the back. Even when there is a chance for going after ‘the common enemy’ like Israel.
India hasn’t even been close to interesting to any of them since the Mughals. The minority Muslim population in India (about 20%) is also just a little less than Pakistans entire population, and almost half of the entire Middle East’s population, so it’s not like it would be a clean ‘attack the Hindu’s’ type situation anyway.
Also, Indians in general are not particularly warmongering, but this is about as righteous a cause as anyone has been able to come up with for awhile to ‘make someone pay’, is total rage bait for the hardliners/Hindutva contingent and is a good distraction for BJP.
As long as it doesn’t get too expensive, or look like it will escalate to Nuclear war, I’d expect it to go on awhile.
India in general loves to get all worked up about Pakistan (and to a lesser extent Bangladesh, though in that case it’s often about illegal immigrants).
It’s a trope like getting worked up about Cartels and/or ‘the illegals’ from down South in the US.
Source: westerner living in India for awhile now. मैं हिंदी नहीं बोल सकता, but I still get around eh?
This won't last long, though. BJP lost the elections after Kargil War.
While this was going on, it even seemed to distract folks in the office from the US H1B situation, which is something.
I suspect both sides will milk this for awhile.
India and Pakistan came to an agreement to stop firings. But pakistan breached it.
I don't think India wants to continue this for much longer.