As with physical defense, sometimes that means diplomacy or sanctions, and sometimes it means executing missions to cripple an enemy's cyber operations. (kpcb.com)
Once a spot is unlocked a talent can't be removed, but you can always swap the same type, so you can swap your earth resistance for fire resistance anytime or give yourself a boost to your magic defense instead of physical defense if you're going up against a powerful enemy who primarily uses magic. (indiehangover.com)
However, like all gunners, the bow user pays a penalty in physical defense. (polygon.com)