In 20th century civil wars (e.g. the Spanish Civil war), telegraph and phone exchanges were strategically important targets. In a hypothetical U.S. civil war, one wonders how successful the belligerents would be in seizing, controlling, or destroying means of communication (data centers, undersea cable termination points, cell towers, microwave towers).

Tech workers, like all workers, would have to make difficult decisions about their allegiances. Let's hope this can be avoided.