Disabled attack- keep the UI?

Like it says, I want to know if there are any good methods for disabling a unit's attacks while keeping the UI display for one. The targets-allowed selection seems to be a bit finicky in that department. Do I just uncheck everything?

Unchecking everything would make the unit able to attack everything. To make an unit unable to attack anything at all, check only the 'Decoration' box and nothing else.

Thanks for that. Just one thing- if the attack has an AoE damage effect, might it damage destructables/doodads that way?