If the balloon goes up, I expect (and hope) the first sign will be the on orbit destruction of the two Nork satellites that pass over the continental US. I bet Act's buddies are shadowing every Nork sub all the time, too
Depends on what they consider about the seriousness of the threat.
Generally, diesel/electrics are considered a local threat. Hard to find on electric, but easy to find when they snorkel.
Adding a mushroom seeder to it though, considerably changes the threat analysis.