Demography strikes me as being quite similar to Torah - easy to interpret however you'd like to, difficult to find the essential truths about which debate is unnecessary. In short, it's more about interpretation than about facts, which, to expand the simile of the previous sentence, puts halachic decision-making, meteorology, and demography in the same subset of hermeneutic masquerading as science.
Such is the context for this piece in Haaretz, which imagines a worldwide Jewish community at 32 million with a strong base in Eastern Europe - and likely no State of Israel - if the Holocaust had never happened. (No word in the article's synopsis on what became of the Jewish communities that were rescued by the Israeli government from the rising tide of rabidly parochial Islam.)
Would the American Jewish renaissance of the last sixty years have existed at all? Would we not be talking about "Jewish continuity" and intermarriage rates? Or would Judaism have been stifled underneath the weight of the iron curtain?
These questions might be addressed in one of Robert Cowley's books recording contrafactual (i.e., What if things didn't turn out the way they actually did?) history (I own What if? and What if? 2 - they're fun). I prefer the contrafactual history to most demography studies, except when someone is willing to get creative, like this work of Calvin Goldscheider, who has argued that the Jewish community in the United States is growing, not shrinking.
As we approach יום השואה והגבורה here in Israel - where the גבורה is emphasized as it is nowhere else - I am inclined to focus more on reflecting on the loss of the 6 million than on naval gazing at what might have been.
As for all of those who wish Anti-Semitic, Catholic or communist Europe had remained the home to Judaism's great population concentration, I remind them of one of Chancellor Emeritus Ismar Schorsch's most astute observations: that never in the history of the world has a Jewish community disappeared by a factor as benign as assimilation.