This week, on the occasion of the International Day of Happiness (yes, there is such a thing), the UN released a study of the state of international happiness. Countries were ranked on a happiness scale from the most to the least. The results were largely to be expected.Denmark, Switzerland, Iceland, Norway, Finland, Canada, the Netherlands, New Zealand, Australia and Sweden were ranked the top ten. What’s not to be happy about in peaceful, prosperous countries with long-established democracies and generous welfare for the needy located in the calmest regions of the world? Immediately after the top ten, however, came a surprise.Little, embattled Israel – complete with its diverse population; its antagonistic neighbors; its limited territory and natural resources; its constant battle with terrorism – was ranked No. 11.What is the source of this happiness? Israelis earn less and pay higher taxes than many countries that ranked lower on the happiness scale. Israelis are burdened by mandatory military service starting at the age of 18 and men do reserve duty well into their 40s. The country was established in the shadow of European Jewry’s destruction and to this day powerful enemies deny the Holocaust while vowing to perpetrate another. And the State of Israel is disproportionately criticized in international forums such as the UN for purported human rights’ abuses, while countries hosting real humanitarian crises go unmentioned by bodies like the UN Human Rights Council.Nor is the UN happiness report a blip. In 2015, the Organization for Economic Cooperation and Development published a survey that examined “general satisfaction with life.” Israel finished in a three-way tie for second place with Norway and Finland. And in 2013, 86 percent of Israelis over the age of 19 said they were “very satisfied with their lives,” the Central Bureau of Statistics reported.At least part of the reason must have to do with the way Jews have learned over the millennia not to let themselves be intimidated by hardship. No holiday better demonstrates Jews’ exceptional ability to remain happy in the face of adversity than Purim. In fact, as Rabbi Jonathan Sacks has pointed out, one of the central messages of Purim is that joy – therapeutic joy – is the best way to cope with trauma.Unlike expressive joy – the joy we feel when something good and positive has happened to us or to our people – therapeutic joy is what is employed on Purim. We are joyous despite the attempt by Haman – with the consent of King Ahasuerus – “to destroy, kill and annihilate all the Jews – young and old, women and children – on a single day.” (Esther 3:13) We as Jews refused – and continue to refuse – to be intimidated by the first attempted genocide of the Jewish people. True, the salvation of the Jewish people was not complete.Even after the deliverance of Purim, the Jews remained under the rule of Ahasuerus, the same king who cooperated with Haman in his plan to wipe out the Jews.This is the reason the Talmud cites for why the Hallel prayer of praise is not recited on Purim.The message of Purim is more complex. Jewish response to the trauma of a barely avoided genocide is not simply to feel relief that this time we were spared a horrific fate. The Jewish way, says Rabbi Sacks, is to “defeat fear by joy... what you laugh at cannot hold you captive.” Terror is conquered by collective celebration.You retell the story of Esther, Mordecai, Haman and Ahasuerus. But you do so while wearing costumes and making noise. You drink a little too much. You fool around. You give treats to friends and neighbors.Of course, the nagging knowledge remains that we still have not reached the promised land, that the salvation is not complete, that there is evil in the world, that Jews are still not safe – not in Israel and not abroad.That was the case in Persia after the “happy” ending of Megilat Esther. And that is the case today. But we refuse to allow this uncomfortable fact to intimidate us.So if you’re searching for the reason why the citizens of the Jewish state scored so high on the UN’s state of international happiness study, Purim might be a good place to start.