You assumed two things. First, you assumed that when the wife says, "We can't afford a new car" that this is absolutely true and not some sort of bias or even purposeful evasion on her part. That doesn't make the husband's approach any more ethical but it does not make his desire to buy a car necessarily irresponsible.

You also assumed I was saying we should spend a lot of money on healthcare reform because Bush spent money on bad things. More precisely, I argue we shouldn't use having overspent money on frivolities in the past as the reason why we can't spend money on critically important things now. If the wife in your hypothetical said their child needed an operation, no parent would argue "they couldn't afford it" because both had bought cars they couldn't really afford in the past. No, they would do what needs to be done because it is the right thing to do.

I do not think the real problem is that American cannot afford healthcare reform but we don't want to afford it even though most of us realize we should make the effort to get it done because it is the right thing to do. "The budget won't allow it" is a cheap excuse in this instance, in my opinion.