What was everyone's personal stake in the war?

[Yorick Brown]

Until later books, it was pretty unclear why the Animorphs, except for Jake and the undiscovered AX, really cared about fighting the war. Sure they had their moral obligation to save the planet but when risking you're a kid risking your life in a wars, there's got to be something in there for you.

-Jake: Obviously, he wanted to save his brother. He was the Animorph everyone most rooted for.

-Rachel: Initially, her reason for fighting was pretty shallow-she liked to kick ass. But after reading The Visitor, I realized that Rachel was now in it to stop the Yeerks from destroying lives like her friend Melissa. So her personal stake was saving Melissa and people like her.

-Tobias: Did he EVER have a real motive? I think he fought simply because he liked having friends and being part of a team; something that never happened  in his pre-Animorph life. He also liked Rachel so that was why he stayed. But his reasons were always very mysterious.

-Cassie: I think Cassie wanted to become an Animorph more for changing into animals rather than saving the world. It wasn't until The Message where Ax told her that the Yeerks would rape and pillage and cleanse the world of animals and habitats that Cassie really started to care about the war.

-Marco: I like his character a lot because he fought with the gang out of loyalty for the group. He was always reluctant but he stuck by though. The Predator changed things though because now he had a good a reason to fight as Jake and Ax and Rachel did: save a life close to him. His reason for fighting now was to save his mom.

-Ax: His motivation was the most obvious of all. He had to avenge his brother. That and all Andalites always had a near religious zeal in fighting the war against the Yeerks was only a plus.

Jake has to save his brother, Rachel had to help Melissa and others like her, Tobias wanted to belong, Cassie wanted to save the planet's beauty, Marco wanted to save his mother and Ax had to avenge his brother and stop the Yeerks as his Andalite duty.

[RYTX]

I peg it down as a sense of duty for all of them:
Duty for someone special (Jake, Tobias and eventually Marco)
Duty for a cause you believe in (Ax)
Or duty to protect something important (Rachel and Cassie)
And on this last point, I associate this to the friendship of the girls, they had a difference sense of how to go about it, but they both place it as this needs to be protected, and we'll do it.
I don't think Rachel jumped in saying "I want kick butt", it was more of, "something's in trouble, and I'm gonna help by kicking butt"
Now Marco, for a start, I'd call it a duty to his friends, but hey, he's a complex guy, I'll never pretend to understand it.

[wotw2112]

I don't know how justified these might be but we could possibly add:

Rachel: To protect her little sisters too.  They were involved enough to imply that they were extremely important to her.

Tobias: He was particularly touched by Elfangor (for obvious reasons) and felt a sense of duty and a need for revenge.

Cassie wanted to protect the earth's animals (the yeerks destory everything) more than she cared for its people.

And well said for Marco: Loyalty at first then his mother obviously.

[XenomorphLV426]

Jake = Tom, plus he's a responsible sonofagun.

Rachel = "action!  adrenaline!  adventure!  meaning!  my friends are doing it!  im there!"

Tobias = Pathetic, pathetic, pathetic boy trying to prove himself.

Cassie  = Save the wooooorld, hippies unite.

Marco = Kidnapped mommy, you're all going to feel the wrath of a gorilla.

Ax = Yeerks die, rabble rabble rabble.

Erek = ancient obsolete and failed programming ethic.