I would agree with this assessment. Perhaps except for the zero. Probability seldom reaches the asymptote.
But just as Keynesian Economics ruled politics for many decades, the anti-science attitudes of today may slowly erode as science does its slow and steady work to solve problems which will not yield to political pressure.
Glacially, perhaps, the realization that we need a larger presence in space may penetrate even the brie and croissant crowd in Washington.
In reluctant recognition that the sun may have something to do with their indisputable Global Warming, they may allow activities intended to ameliorate the effect. It is, after all, hard to blame global warming on Mars on those ubiquitous SUVs here.
You misunderstand what I'm saying to some degree - my fault. The major reason for the (almost :-) zero chance of a big US science effort has very little to do with the Washington, DC crowd. It is the science community itself that squashes such an idea! When I make such comments as, "The US has the ability to do this by ourselves..." to the very good scientists around here, they unfailingly look at me as if I must be drunk! Research scientists seem to lack any confidence in the United States' ability for accomplishment in the absence of major international support. (Three examples where I've seen this relatively recently: Missile defense, Fusion, Large Acclerators)