Timeliness, for one thing.
Take airbags in cars, which are comparatively much cheaper than the sorts of changes required to make buildings, buses, etc. wheelchair-accessible. The automakers suddenly came around on them in the early 1990s, but they could have been mandated as early as the late 1970s at a low per-unit cost. If they had, probably tens of thousands of people would be living who are now dead, and hundreds of thousands would have escaped serious injury.
Given the greater cost and difficulty of handicapped access, it’s a good bet that the lag between when it could be mandated, and when a critical mass of businesses would choose to provide it on their own, would have been much longer than the fifteen years for airbags. What the mandate gets you is an entire generation of wheelchair-bound people being able to live more or less normal lives, as opposed to hardly being able to go anywhere without assistance.
Whether that’s worth the ‘tyranny’ of a government mandate very much depends on how you see the world, of course. But in both examples, the societal benefits are nontrivial.
Another example: since our starting point is America at the end of WWII, it’s worth recalling that America at that time was a far more racially segregated society than it is now. While public opposition had a great deal to do with changing that situation, it’s worth remembering that public sentiment forced sweeping changes in the laws, which forced white people to employ Negroes, let them buy houses and rent apartments, admit them to their schools, and otherwise put us whites in situations where we eventually had to recognize (and I’m not being facetious here) that persons of African descent were genuinely human, rather than some sort of half-man, half-ape, which ultimately made discrimination unacceptable as well as illegal.
How would this have been if America had been a libertarian wossname? The South had preserved Jim Crow for a century after the slaves were freed; what was to stop them from doing it for another century? Even assuming the absence of Jim Crow laws in a libertarian USA, we know it wasn’t just the laws that maintained Southern segregation, but a climate of fear as well. Would the central government have the authority, in a libertarian USA, to enforce the equal rights for blacks that the Southern states would have been unwilling to enforce? Would the South, under a libertarian system, simply secede, without contest this time, and be free to cease being libertarian with respect to race? And how much more slowly would de facto segregation and unequal enforcement of the laws in the North have ended? (It still continues, after all.)
In the long run, things would have surely changed. But as the long life of Jim Crow demonstrates, in the long run we’re all dead. Justice delayed for a lifetime is unquestionably justice denied.
