Cooper Howard was arrested in the Fallout TV series because he was targeted by the House Un‑American Activities Committee (HUAC) as part of a political smear campaign tied to his suspected communist sympathies and his knowledge of the U.S. government’s secret cold‑fusion and nuclear‑war plans.

What the show says

  • Cooper is arrested on the authority of HUAC, a real‑world‑style committee that investigates alleged disloyalty and communist ties.
  • In the show’s lore, he is branded a “communist” or “un‑American” figure, which is used to destroy his reputation and silence him.

Why he was really arrested

From the narrative perspective of Fallout Season 2, the arrest is less about actual crimes and more about damage control by the Enclave‑aligned establishment:

  • Cooper knows about the Enclave’s unlimited energy source (cold fusion) and the broader nuclear‑war strategy, making him a threat if he talks.
  • By arresting and publicly shaming him, the authorities aim to:
    • Discredit anything he might reveal.
    • Isolate him from allies and the public.
    • Pressure him to stay quiet or reveal more about his contacts.

How it affects his life

  • After the arrest, he is blacklisted , loses his career, and ends up hosting kids’ parties while being mocked as an “alleged communist” struggling with alimony.
  • In the canon, he also takes the fall alone to protect others (like his wife Barb), which deepens the sense that his arrest is politically motivated rather than based on genuine wrongdoing.

So, in short: Cooper Howard was arrested because the U.S. government‑linked powers used HUAC‑style tactics to silence and discredit him after he learned too much about their secret energy and war plans.

Information gathered from public forums or data available on the internet and portrayed here.