You're imagining what is essentially an impossible scenario, because your setup is factually badly wrong. The ransomeware attack in question wasn't capable of

You're imagining what is essentially an impossible scenario, because your setup is factually badly wrong. The ransomeware attack in question wasn't capable of shuttering the pipeline as a target, whether the hackers wanted money or not. That was a voluntary action by the company, a questionable precaution they chose to take. The US military isn't directly restrained by that pipeline. They have their own fuel supply lines that do not particularly care about that specific pipeline. And even if they did, they can go to the source, they don't require that pipeline for fueling purposes. They have other means of mobilizing refueling, up to and including anything that is necessary from a transport, manpower and logistics standpoint (including commandeering approximately four zillion private fuel trucks and tankers to get fuel moving for defense purposes). There is no scenario where that pipeline existing or not existing tomorrow would shut down the US military or prevent its ability to defend against an impossible and amusingly implausible attempted land invasion of the US domestic territory. So, imagine if that was a nation state (uh, which one?) mobilizing for an invasion that can never happen, an invasion that could never get across the Atlantic or Pacific. No. Bombs start falling? From where? China? Russia? Russia is doing what, invading the east coast? With what ships? With what air cover? With what magical clandestine capability to hide a massive military as they sneak across the Atlantic on non-existent ships. With what aircraft carriers? And with China, so the US sends bombs back the other direction. The ability to throw a thousand nukes at China isn't restrained by the East Coast pipeline, and they know that, as does every other nation on the planet. Again, your setup is so far outside of reality that it's absurd.