Libertarianism
USEFUL. 1) There is No Free Lunch - "free stuff" has to be paid for; 2) foreign interventions must always be viewed with suspicion; and 3) government subsidies create constituencies that make them difficult to liquidate or even cut back. Look at the fate of Hagel's modest efforts at military reform.
DEAD 1) the fetish of deregulation; 2) use of lawsuits to curb pollution - after the fact; and 3) (I must step on some toes here) the cult of the charlatan Ayn Rand, who absurdly claimed to be a universal genius.
Concededly, this tentative inventory is but a sample of a work in progress,