Class discussions about the war

There's a particularly timely post on Blogher about the cost of the Iraq war - and I say 'timely' because I was in the middle of thinking about how to talk about the war in my class when the post appeared in my reader. The post links to a calculator from Progressive Future that tells you how much of your 2007 taxes went to pay for the war and what that money could have bought in terms of days of health coverage, Head Start, renewable power or education for a veteran. The calculator highlights the dollar value of these alternatives but the post on Blogher also points out that it's hard to put a dollar figure on some of the other costs. That was going to be my point in talking about the war in class - I'm planning to use the war discussion to tie together cost-benefit analysis with the positive-normative distinction (i.e., how much you value certain costs, like the loss of American lives, versus the benefits, like increased safety, is really a normative assessment). I stress to my students that economists try to stay in the world of positive analysis - identifying what the costs and benefits are, particularly making sure everyone recognizes the trade-offs involved - but policy decisions often come down to normative values.

However, whenever I venture into controversial topics, I get very nervous. Obviously, discussing sensitive topics raises opportunities for students to get offended, or make offensive comments. I try to set discussion ground rules early in the semester, and reiterate those again before discussing certain topics, and I try to keep the discussion focused in a fairly narrow way (e.g., identify the costs, identify the benefits, identify which can be measured objectively and which are more open to value judgments, etc.). I also try to be very clear that I am not saying that X is right or wrong. Discussions can easily disintegrate if students do not understand that I am not trying to convince them that one position or the other is 'right' but that I am trying to clarify what the factors are that might lead one to choose either position. One thing I always find a little ironic is that I have often had students on BOTH sides get upset because they believe I am supporting the view opposing their own (that is, because I am not clearly endorsing their view, they assume I am implicitly endorsing the other). On the one hand, the fact that students on both sides feel this way tells me I am doing something right; on the other hand, the fact that any student feels this way tells me they have missed the point so I must be doing something wrong.

I'm curious how others handle discussing topics that could be considered controversial. Do you even attempt it?