Well, my argument came down to this:
Nobody is forcing anyone to do anything.
If you don't want to get health insurance, you don't have to. But guess what, you're going to have to pay a tax. This went back and forth ("How come I have to pay for your health insurance if I don't want any?"). The other concern is the price tag.
Yeah, $1 trillion is steep. But a few things - it's a drop in the bucket compared to wasteful crap like TARP, Iraq, etc.
Also, more importantly, it's probably nothing compared to what our generation and future generations would have to pay in health care costs once an entire generation of poor nutrition and no preventative health care become eligible for Medicare. Yes, I would rather foot the bill now, than have to pay ten times that amount twenty years from now.