I guess we'll never know because half the country didn't even try.The smallpox vaccine was highly effective, and you're right, local quarantines helped control outbreaks, especially since smallpox had clear transmission patterns. Back then medical teams could isolate communities relatively easily too. However, the context of quarantining during smallpox (which was before our current economic structures) was very different. Back then, shutting down a small town didn't have the same widespread economic impact as shutting down a major metropolitan area today.