For what it’s worth, I don’t think it’s quite fair to say that NATO’s push to get the Dutch to extent their troop deployment to Afghanistan was “the cause” of the breakdown of the grand coalition that had been governing the Netherlands. Rather it looks to me like Prime Minister Jan Peter Balkenende rather cleverly found a way to use it as a pretext to shift the political situation to his advantage.
Basically now he’s created the circumstances where the Dutch military will leave Afghanistan, which is what most Dutch voters want, but wherein he also gets to blame the Labor Party for having forced this situation and diminished the Netherlands’ standing in the eyes of NATO and the United States. He has a good talking point in which he can accuse Labor, his main partner in the coalition but also his main political rival, of irresponsibility while also reassuring the voters that the troops will be coming home one way or another. Normally when a grand coalition breaks down in this way, you’d expect the party that was pushing the divisive issue to say something like “Give us Christian Democrats a bigger majority so we can continue the war in Afghanistan,” but Balkenende isn’t saying that at all—he’s saying that now that there’s only a caretaker government in place, the troops will have to come home on schedule. And any new post-election Balkenende coalition is overwhelmingly likely to depend for support on one or more anti-war parties since both the Dutch center-left and the country’s growing far-right party all oppose continued military action.