JERUSALEM – I knew that it was time to try to explain to readers of the Press Herald the inexplicable goings-on between Israel and the Palestinians after I received a Facebook message over the weekend from John, an old friend of mine from Portland High School’s Class of 1977.

He expressed concern for my safety in Jerusalem and wondered what happened to launch this current round of warfare between Israel and terror groups in the Gaza Strip, led by its governing body, Hamas.

Well, John, since you asked … it’s indeed a shame that most people don’t know why Israel launched Operation Pillar of Defense six days ago.

While I am fine — and aside from one warning siren sounded in my suburb of Jerusalem on Friday night, out of harm’s way — the same can’t be said for well over a million Israeli citizens in the southern part of the tiny country, about the geographical size of New Jersey.

Evidently it hasn’t been reported in local U.S. papers or media that over the last few months, Hamas and its terror cohorts have been firing hundreds of missiles into Israel, hoping to kill as many people as possible — whether they be soldiers, women or children.

We’re talking about almost 15 percent of the country’s population having to regularly run to bomb shelters, including mothers who are suffering from chronic post-traumatic stress disorder and children who are traumatized by the shrieking sirens and the subsequent booms of the Iron Dome defensive shield system (thanks to U.S. assistance), which miraculously is able to explode most of the rockets before they have chance to land and do damage.

Imagine what the state of Maine would do if Canada began indiscriminately lobbing deadly rockets into the barren northern Maine frontier, where hardly anybody lives. How many rockets would it take to prompt a response?

In Israel’s case, the reaction has been one of unparalled restraint, until it just no longer was possible. So on Nov. 14, after some 100 rockets fell on southern Israel in a 24-hour period, wounding three residents of Sderot, the Israel Defense Forces launched Operation Pillar of Defense, aimed at restoring quiet to the country’s southern border.

Air force sorties targeted Hamas military chief Ahmed Jabari, who was responsible for the rain of rocket fire on Israel, and in response, Hamas escalated their attacks on Israel.

And only then did the world’s media began taking interest — which is why my friend John didn’t know why Israelis and Palestinians were suddenly killing each other.

President Obama put it as eloquently as anyone when commenting on the situation after arriving in Thailand over the weekend.

“There’s no country on earth that would tolerate missiles raining down on its citizens from outside its borders. So we are fully supportive of Israel’s right to defend itself,” said Obama.

And the manner in which Israel defends ranks right up there with the U.S. armed forces in its goal of rooting out terror while making every effort to minimize civilian casualties.

That’s the mirror opposite of the Palestinian terror organizations, which intentionally embed themselves in the heart of civilian populations, store missiles in hospitals and schools and callously use mothers and children as human shields.

The Israeli army showered Gaza with leaflets calling on innocent civilians to leave areas where Hamas operatives were hiding, and took over Hamas radio stations to make similar pleas.

However, on Sunday, during an attack on a Gaza building that Israeli media say housed a senior Hamas official, the Israeli air force killed 11 innocent civilians, including women and children, in a horrible, avoidable tragedy.

Every Israeli felt sick after hearing that news, the exact opposite of how the Palestinians celebrate when their missiles intentionally murder equally innocent Israelis.

But there’s the rub — for these Palestinians, no Israeli is innocent, and as long as Israel exists, they will make every effort to destroy it.

Moves for a cease fire are under way, with senior U.N. and EU officials in the region to push for both sides’ acceptance, before an Israeli ground invasion into Gaza is implemented.

Whether quiet is restored today or in the coming days, eventually there’ll be some agreement, just like there was after 2008’s Operation Cast Lead, the 22-day campaign into Gaza by Israel after a similar period of Hamas rocket attacks became intolerable.

And you can be sure that some point not far down the line, the situation will repeat itself. Palestinians will begin firing missiles at Israel once again. It may be one or two a day, then gradually escalate into a dozen and then a hundred.

And only when Israel is finally forced to retaliate, I’m sure that John will drop me a Facebook message asking why Israel and the Palestinians are at it again.

David Brinn, a native of Portland, is the managing editor of The Jerusalem Post.