I agree those people are foolish, but my statement was about the relationship between terrorists and the state.

1. A state like the US will always have more firepower than a single terrorist group.
2. A population where everyone is armed will also almost certainly have more firepower than a single terrorist group, too.

The power dynamic is between the terrorists and anyone who would oppose them, not just the state. You also reference police, when terrorists are basically always ultimately handled by a military force, which will have a monopoly on violence regardless of how one ignorantly attempts to organize or arm their police.