Left2Right Comments

Your comments make me think of something that Thomas Nagel wrote in the preface to his book of essays, Mortal Questions. He writes:

"Moral judgment and moral theory certainly apply to public questions, but they are notably ineffective. When powerful interests are involved it is very difficult to change anything by arguments, however cogent, which appeal to decency, humanity, compassion, or fairness. These considerations also have to compete with the more primitive moral sentiments of honor and retribution and respect for strength.... So I am pessimistic about ethical theory as a form of public service. The conditions under which moral argument can have an influence on what is done are rather special, and not very well understood by me.... It is certainly not enough that the injustice of a practice or the wrongness of a policy should be made glaringly evident. People have to be ready to listen, and that is not determined by argument."

Perhaps sentiments like these are what have caused so many academic philosophers to remain in their ivroy towers: our attempts to enter the real world are ineffective because so few people are willing to listen.

Of course, Nagel has not remained in his ivory towe, but has provided real contributions to political discussions. And this passage does not justify isolationism on our part. Rather, it helps to make sense of the fact that so many academic philosophers remain isolated.
 

Its interesting to note that in Scott's comments regarding Nagel, he cites Nagel contributions to political discussions. Political discussions are a bit different from first-order ethics. This is not to say that there isn't a connection between ethics and political philosophy; the connections are very deep, strong and important.
But there is one fairly clear difference between first-order normative ethics and political philosophy: first-order ethics' subject matter is the decisions and actions of (usually) indiviudals. Political philosophy does not look at individuals in the way that normative ethics does. Though some topics in political philosophy, like political obligation, the duty to obey the law, concern the relationship and duties of the individual as concerns the state, political philosophy is generally concerned with the acts of social power structures - governments. (This is not to rule out the possibility that there may be group structures employing power and force that may be the subject of legitimate inquiriy by political philosophers; Nozick's hypothetical protection agencies might be such a case.)
It seems to me that philosophers may have had more success in political philosophy than in first-order normative ethical theory, when it comes to giving practical advice. None of my examples are slam dunks, but I think what I have here are some fairly good ideas.
Consider:
While the morality of having an abortion is intenseley debated as an issue in first-order ethics, political philosophers have come in quite heavily on the side of saying that the state is not justified in restricting it (at least not beyond a very few limits). I can't think of any influential philosophical work in favor of governments banning abortions.
The death penalty. Legal and political philosophers have weighed in, again heavily, on one side: against. I am aware of some work that advoces retributivist views that approve of the death penalty, but I can't think of any of this work that is considered especially good or comes from top-notch philosophers.
Lest someone accuse me of a liberal bias, I will readily admit that there is good work by philosophers that raises problems for "politically liberal" views. David Velleman's work on euthanasia is a perfect example. It is a piece of excellent work by a philosopher generally considered to be in the highest echelon. Prof. Velleman's paper, while not moving me to change my position on the issue, forced me to think about how to respond to the problems he raised, and to recognize that there are genuinely good arguments opposing mine, raising issues that deserve our attention.
My view, to summarize, is that moral philosophy seems to make its most significant practical contributions when done as or in conjunction with political and legal philosophy.
 

It's certainly safer, and seems wiser, to deny that theoretical moral philosophy can't help us resolve moral dilemmas. But then what about the counter-examples?
We know our vote won't make a difference, and we have another moral duty to attend to on election day...how do we decide what to do (eg. what's the import of "What if everybody didn't vote" type questions). This is a question for professional ethicists.

Or suppose we are contemplating whether it's wrong to kill a fly, particularly if we're committed to vegetarianism. Or whether we should be vegetarian at all, or give away more money to Oxfam on a weekly basis, or not buying Starbucks, etc. These questions -- especially re. vegetarianisms -- have been answered by moral philosophers in a way that offered useful guidance for many people. I know that's not proof that they should have been, but I think Peter Singer's work provides a useful counter-example either way.