As the title says;I've recently started wondering on this subject. Christianity is currently the number 1 religion of the world and Islam isnt all too far behind. History was riddled with Christian and Muslim civilizations and they were major players in history. There are stilI a couple theocracies in the world today; yet judaism never achieved any of these. Why?
While more can be said, /u/hannahstohelit gave a great write-up a week or so ago on the internal and external reasons for Judaism’s smaller numbers here: