You can find the best argument for the feasibility of private financing of public goods in Anthony de Jasay’s 1989 book Social Contract, Free Ride: A Study of the Public Goods Problem (Clarendon Press). As a bonus or a malus, you will also find there an argument against social contractarianism à la Buchanan. De Jasay’s book is a technical book, not necessarily easy to read and not without flaws. I summarized the argument and offered a critique in a recent Regulation article (see pp. 60-62). In a few words, let the individuals who don’t want to risk being deprived of a public good contribute to its financing and let free riders enjoy their free ride. (After all, aren’t we “inclusive”? Equal liberty for everybody!)

An Economist article just provided an illustration of partial private financing in the most difficult case of public goods: territorial defense. The story is about the development shoebox-size listening stations that detect the sounds of attacking objects, analyze them with smartphones or microcomputers, and transmit the results to Ukrainian air-defence operators (“How Ukraine’s New Tech Foils Russian Aerial Attacks, The Economist, July 27, 2024):

Kyivstar, a telecoms firm, installs Zvook’s kit on its cell towers, handles maintenance and transmits data all free of charge. …

A far bigger acoustic-detection network has been developed by a secretive Ukrainian outfit called Sky Fortress. It consists of several thousand listening stations, with thousands more planned. Though its initial listening stations captured and processed sound with Android smartphones, the network, like Zvook’s, now uses dedicated microphones and microcomputers. Data are fed into a Ukrainian command-and-control system known as Virazh. Like ePPO and Zvook, Sky Fortress is mostly funded by donations, an astonishing development for air defence.

Few outside experts are privy to Sky Fortress’s workings. One of them is Riki Ellison, founder of the Missile Defence Advocacy Alliance (MDAA), a non-profit in Alexandria, Virginia. Sky Fortress has become so extensive and “so damn good”, he says, it now detects most Russian munitions that fly low into Ukraine. Russian units have begun to muffle or otherwise alter their drones’ acoustic signatures, but the detection algorithms promptly adapt. “This is AI at its best,” says Mr Ellison.

The crucial sentence is the last one of the second paragraph quoted above: “Like ePPO and Zvook, Sky Fortress is mostly funded by donations, an astonishing development for air defence”—even if the restrictive “mostly” suggests that public financing is also involved. The Economist’s article does not say whether the voluntary contributors are Ukrainians or their supporters elsewhere in the world, which would further inform us on the general possibility of financing public goods privately.

Ukraine is not the rare bird called a free society, but it is certainly freer (or less unfree) than, say, Russia—free enough that we can see how independent innovation and private action is making a difference.

Note that a public good for some is not necessarily a public good for others, like for the invading army in the present case. This observation further supports the general idea of letting individuals in ordinary social life free to each finance what he wants if he thinks it is worth it for himself (whatever his motivations). Note also that even in the freest of free societies, defense against international tyrants and thugs would be required—as I tried to illustrate with a fable in a recent post (“From the Fourth Millennium, A Tale for Libertarians”).

I am not claiming that these ideas necessarily solve all the problems of politics. But they cannot be ignored.

Acoustic detection of air attacks in Ukraine

Acoustic detection of air attacks in Ukraine, with artistic license and AI glitches