I was just thinking ... Animorphs had profound influences on many of its devoted readers as they grew up.
There are some fairly deep underlying political themes in the book which are presented relatively simplistically for the youth audiences. I wonder to what degree KA has shaped a small generation of young adults in their perspectives on politics, the Iraq war, voting patterns, etc?
Thinking about it now, KA must be something of a liberal. She was born in the 50's, so is a baby boomer who would have been strongly influenced by the events growing up in the 60's such as the US civil rights movement, progressive agendas and the Vietnam War. I can think of at least a few instances where such themes crop up in the book:
1) Multiculturalism, prejudice and racism: Jake/Cassie relationship. Even numerous beautiful inter-species relationships such as Elfangor/Loren, Dak/Aldrea where key characters show the reader that true love can transcend the most stark cultural and physiological differences in classic Romeo/Juliet subtexts.
Ax is negatively portrayed for his views on a disabled Andalite and reprimanded by the other Animorphs for doing so, but is 'enlightened' through communicating with him, eventually respecting him as an equal.
There is also sporadic commentary on the nature of human discrimination in several books on the issue of various aliens such as the Hork Bajir living amongst humans.
2) Feminism: Andalites are a highly patriarchal however 'old fashioned' beliefs regarding the role of women are slowly changing during the war eg female warriors. In THBC, Aldrea, the protagonist is a smart, bold and adventurous heroine who is unable to be taken seriously by the highly masculine Alloran which leads to disastrous consequences. The patriarchal nature of Andalite society is not generally portrayed positively. Further, Rachel's 'warrior' characteristics contrast with her lover Tobias, who was something of a wimp as a human and a bit soft. KA chose a female to represent the most violent and boldest animorph (although not the leader).
3) No clear Good Guys/Bad Guys... Enemies are people too: KA provokes her young audience to consider the Yeerks as multi-dimensional enemies - fighting for a better life, as well some who seek peace. Even though they are parasitic slugs, they have good guys as well as bad guys, just like every side in a war - The subtext being that all sentient beings (i.e. humans) are not that different, and that much of war is the result of misunderstand and lack of communication. The ultimate resolution to the war was to give the Yeerks morphing power.
4) Military Empire and American Foreign Policy: Some rough parallels can be drawn between Andalites (United States) and Yeerks (Soviet Union). The former are the galaxy's policemen - governed by the presumably democratic 'electorate' i.e. the people, the latter are an empire ruled by a ruthless dictatorship where generals kill their internal opponents and dissent and incompetence is brutally punished. Although Andalites start off as saintly good guys - the more 'real', arrogant and self serving they appear through the series. This is particularly true of their leaders. The loss of the Hork Bajir world draws comparisons to the US retreat in Vietnam - innocent lives being sacrificed in the name of war. Alloran in TAC is something of an Andalite version of the jaded Vietnam veteran after the events of THBC (although by no means converted into a hippie).
The story of the Hork Bajir in particular has something of a noble savage element to it - a strong, powerful species that lived in complete peace as innocent bystanders until war was brought upon it by technologically superior powers. i.e warring European nations carving up Africa.
I wonder if this has influenced how readers here interpret current world events? Young people are generally more liberal than older people, although my guess is that Animorph readers are more likely to be more accepting of diversity, probably more anti-war, and perhaps a little more cynical of recent American foreign policy. I think, for example, Animorph readers would be less inclined to buy into an 'us Vs them' mentality when thinking about the Muslim and Arab world, as conservatives might see the conflict.