So ... you’re saying this could really be a crisis?
More dangerous would be attacks on physical infrastructure like the fiber lines going into MAE-East and MAE-West. A backhoe, and a judiciously planted quarter-pound of C-4 could really hose things up. Primarily because so much traffic is routed through a limited number of points (at the demand of our feral government to aid their surveillance state). If someone just cuts a bunch of fiber, it can take hours to fix. If you make an attempt to destroy the cable with explosives or whatnot, you could be looking at a bit more time to recover. Fortunately, much infrastructure can be routed around, but by design, some of it is more difficult to deal with.
Even in that case though, I don't see the damage not being fixed after a week. However, even if we recover in a relatively quick time frame, you have to keep in mind that with just-in-time inventory management, some cities would be virtually out of food in less than a week. That's not a good thing when you have large portions of our largest cities that are effectively barely civilized.
There are other ways to attack infrastructure as well, that many people don't think about. A dedicated adversary could screw things up really badly. Let's say you hit big internet infrastructure both physically and logically. This generates a bit of chaos, to further feed that chaos, they might also hit a bunch of the really large transformers across the country. Most people don't know that in many cases, those transformers are custom jobs largely imported from asia (japan). In some cases, there really isn't a hot spare available, especially if someone takes a site out in a determined manner. Dropping a bunch of legs of the grid like that will likely cause most of the rest of the grid to fail as well. How long to replace 50 large multi-million dollar custom built transformers? Months? Years?
Our civilization skates along on a thinner edge than most people are comfortable with thinking about.