It's pretty darn clear we got ops going on in the Vatican and Pakistan. The blackouts are cover. It's also pretty clear @Jack has some serious karma coming to himself and his little business from POTUS. I think it likely that Twitter will be raided but not until the net is largely taken down to prevent a huge barrage of pre-canned tweets from whining about gestapo tactics.
So I think it's likely the net will be taken down in a few days and for a few days to cover some serious ops. That's when and why the EMS will be brought into service. When the net comes back up, twit and goog and fb and the rest their kind will have been cleansed of their censorship and free speech will be back.
It's possible to take down the sites without taking down the internet. Easy? No. They're so intertwined with every other site it would take some time to get it done correctly. CDNs, Geo-redundant data centers... Yeah.
Easiest way would be to take down the internet... But even then if you just shut down/disabled DNS it would be just as effective. How many people know the IPs of their favorite site... 1/100000? Even then, some web hosts require headers and refuse to serve when an IP is entered.
Well there are somehow easier solutions, you can reverse network blocks assigned to entities, and knowing ones used by FB & Friends is not so hard, collectors / frontends are on static address space, you don't care about a CDN or if they have a hot site somewhere, cause you literally block connections at ISP or national IXP level, take in consideration, they could for example stop twitter in the US, but that won't affect the entire world, only way to do so is to dismantle the company, otherwise they will always have subsidiaries and offices around the globe that can restore / continue operativity, business is to big
It's very easy if you have access to the backbone routers.
See China
Yup i do understand for the US, that's why i mentioned national IXP, but was explaining that still, even if X countries get "disconnected" the network will still be on in other countries or continents ( of course with relative disservices in case of decentralized app / sites etc )