Once tikkun olam was an obscure mystical idea known only to Kabbalists, now it's the official culture of American Jewry.

In a White House proclamation announcing Jewish Heritage Month this month, Barack Obama saluted Jewish Americans who "today… carry on their culture's tradition of tikkun olam - 'to repair the world' - through good deeds and service". 

He signed it "in the year" 2010 rather than the usual formula, "in the year of our Lord".