To begin, let me note that I think Matt is right that understanding the empirical facts will not be enough to bridge the gap between modern, welfare, liberals and libertarians, even we bleeding heart libertarians.  I also doubt that understanding the empirical facts will be enough to bridge the gap between other libertarians and we bleeding heart libertarians.  Values matter.  Some values matter more then others and some of the disagreement is about that. I believe that two moral values, in particular, are more important than others: autonomy and eudaimonia.  If I am right, these ground my normative views–moral and political (in the latter, I think the central value is toleration–but that view is meant to be grounded in the moral view).  To my mind, though, it is an unfortunate fact that autonomy and eudaimonia are undervalued in our society and so not as common as they should be.  And so the question: what would help these become more common and more valued in our society?  Before answering, let me explain a bit.  Much of this will be necessarily sketchier then I would like.

There is a difference between saying "X is a value" and saying "X is valued."  People may fail to value autonomy and eudaimonia even if they are, objectively, values.  Here I just assume they are.

People like to say they should be free to choose what they do.  I think choice is a good thing, but only when it is autonomous.  The choices of my dog are not.  The choices of Joe, who one moment decides to work to get into law school, the next moment decides not to do that but to work to get into med school, and the next moment decides to do neither of those, but something else, and on and on, are not.  Because he lacks autonomy.  And here's a problem: too many people in the world lack autonomy.  Some lack autonomy because they lack nutrition and other prerequisites.  That's a real problem (especially in the third world but also here).  But there also seem to be a lot of people in the west who lack autonomy (perhaps not as badly as "Joe") even though they lack for nothing material.  There is, I think, an anti-intellectualism in the West (perhaps especially the U.S.) that causes too many people to not seek to develop their critical reasoning abilities–another important prerequisite for autonomy.  Many do not value either ability, though they are objectively valuable.  (Importantly, that they are objectively valuable does not mean everyone is better off with them.  Hence, I am wary of attempts to force people to be autonomous and favor a system where people find themselves choosing autonomy on their own.  The state should toleration those that choose not to.)

Critical reasoning skills are also important for eudaimonia: the well-led life.  In our society, people seem to think that what matters is being "happy," where this is simply a state of mind.  But people can be happy leading quite bad lives.  Jill, for example, thinks she has the perfect marriage, children, health, job, etc.  In fact, though, she is about to find out her husband is cheating on her, her children are drug addicted killers, she has an aggressive form of cancer that will leave her racked with pain for her remaining days, and she has been fired for incompetence.  Not realizing any of this, she thinks she has a good life.  She is "happy."  She is not leading a good life.  Perhaps if she was a better thinker, she would have chosen differently.

So the question: what what would help autonomy and eudaimonia become more common and more valued in our society?  One answer should be obvious: an improvement to the critical reasoning skills of everyone in our society.  I would suggest that closing down philosophy departments (Nevada) and telling people that college profs are lazy (Wisconsin) is not going to help in this regard.  I would also suggest, though, that encouraging parents to think the government will take care of their children, by providing them day care & education (and meals & health care in the day care or school), will also not help.  People need to be encouraged to take responsibility for their lives and the lives of their children and that does not happen in a "nanny state."  When people are encouraged to take responsibility and allowed and encouraged to develop their critical reasoning skills, I submit, they do so.  And when they do, they develop their autonomy and choose better, leading them to eudaimonia (or, at least making it more likely that they will reach it).

Other answers welcome.  Also welcome: suggestions of values that matter more than autonomy and eudaimonia.  Material wealth would not, I should note, be such a value in my view.  (Of course, I think material wealth matters, but because it makes it possible for more people to have autonomy and eudaimonia!)  I can guess at some of the other more plausible options, but none strike me as more important than the 2 I have discussed here.  Some of my co-bloggers may disagree with that, which I think only indicates how much disagreement about values there is.  Of course, even if we agree that these 2 values are the most important, we may disagree about how either or both is best understood.  Certainly, alot of Rawlsians claim to value autonomy–but I suspect we would disagree about what it is.  Some on the right likely value eudaimonia–and again I suspect we would disagree about what it is.