But what’s so wrong with textbooks anyway? It’s not so much the simplification itself. All theory (including some much-lauded high theory) does that. Nor is it any particular problem with the qualifications of the authors (the contributors to Baylis, Smith and Owens, for example, are pretty well the dominant names in their respective sub-fields).
Still, textbooks do seem to take on a strange epistemic authority, at least in undergraduate study. Confused by the relationship between ethics and self-interest in Morgenthau? Settle it with some bullet-points! IR is a young discipline, and none of its canonical texts approach the difficulty of, say, political, social or cultural theory proper. Any competence is going to come from understanding those texts, so why not do it sooner rather than later? Moreover, the relentless simplifications of the ‘paradigms’ debates (can we drop the mutilation of Kuhn yet?) provide an easy tool for obliterating complexity. This is not unrelated to a patronising attitude towards students, gently shepherded through the early years before being told harsher truths.
Textbooks, especially ones recommended at the start of courses as the intellectual crutches of choice, reinforce those dynamics. But it gets worse. Textbooks also lie.