I would say that the analogous objective of rationality is to protect oneself from mental threats: dark arts, misleading questions, tempting but wrong arguments... where specific biases would constitute specific types of attacks.

A couple interesting corellaries from that line of thought: 1) like in a physical situation, mere awareness of the form an attack may take doesn't always help; 2) like martial arts, in mental defense you have the option of developing a large number of highly specific defenses, or a smaller number of more generic ones

It does seem a little limiting to consider rationality nothing more than a mental form of self-defense, but I would argue that the higher levels of martial arts offer far more than that, and like rationality aim (among other things) for holistic life improvement.

An anecdote from my martial arts background:

A student asked, "Sensei, what would you say if I came into the dojo tomorrow and told you I had been attacked in a dark alley, and that I had protected my child who was with me, and defeated my attackers, and escaped unharmed?"

The teacher responded, "I would say that I had failed you as a teacher, because the ultimate goal of our art is not to defeat attackers, but simply not to be present when the attack comes."