I think the low probability explanation is more plausible than the commons explanation. Scientific funding for non-classified projects -- which constitutes mos

I think the low probability explanation is more plausible than the commons explanation. Scientific funding for non-classified projects -- which constitutes most funding -- is partially a contribution to the commons. The development of human capital on the home front is a unique benefit to the funding country, but the results get disseminated and -- in principle -- there's nothing stopping a company in another country from commercializing first. Also, I agree the politics of asteroids are really inractable. Lots of people think of asteroids as a plot device for egg-head sci-fi fans rather than an actual existential threat. (FTR, I think that, in general, we should be doing a better job as a species at buying insurance policies to protect ourselves against extinction-level events.)