You could also say that the Aiel were hesitant about hanging around with the Shienarans who predominated both those scenes, due to their long enmity, but whose fault is that? The Three-Fold Land borders on three (four until recently) wetlander countries. And which one do the Aiel raid? Cairhien who offered them mortal offense in the last generation? No. Ostentatiously wealthy Tear? No. Shienar and Malkier, who were probably the two poorer of the four lands bordering the Dragonwall, and thus have the least loot, and who are mostly occupied with trying to fight the Shadow? Yeah, let’s pick on THEM! The Shienarans do not raid the Three-Fold Land, as they seem to believe it isn’t worth having, and see the aforementioned struggle for their very survival against the Shadow as their paramount concern, leaving them no spare resources to fritter away attacking the Aiel. There is no motivation for the Aiel to raid them that does not apply to lands they leave alone, but they exclusively raid Shienar. They have peaceful trading relations with Shara despite getting cheated at every opportunity, they give gifts and rights of passage to a nation that couldn’t give a damn and they harass and harry the nation that is desperately trying to hold back the forces of the Dark One. Way to go, Aiel.