Both Prime Minister Binyamin Netanyahu and Defense Minister Moshe Ya’alon have said over the past two days that Operation Protective Edge will not be over quickly.“This operation may take time,” Netanyahu said in a taped message on Tuesday night. And on Wednesday morning, Ya’alon said, “From our standpoint, this is a campaign that will not end anytime soon, and we must continue to maintain stamina and patience.”The operative words in Ya’alon’s comment were “from our standpoint.”After waiting a number of long days before launching a widespread military operation, now that it has begun both Netanyahu and Ya’alon want to deliver a blow that Hamas will remember, and that will deter it – at least for the foreseeable future – from disrupting the lives of millions of Israelis with random rocket fire. And that type of operation – that will send the type of message Netanyahu and Ya’alon want – will take time.But there is no certainty Israel will have that time.What Israel has learned from its experiences with small-scale military operations in the past – be they in Lebanon in the ‘80s and ‘90s against Hezbollah, or in Gaza since 2005 against Hamas – is that time is limited.The media is already beginning to broadcast a grisly “scorecard” of the number of Palestinians killed in the operation, and this will soon be followed by comparisons with Israeli casualty figures (none so far, thankfully).What will go unreported is that the imbalance in these figures is partly because while Israel invests billions of dollars to protect its citizens, Hamas uses civilians to protect its rockets. But those pictures and that scorecard all have an accumulative impact.Go tell the world that the Palestinians are responsible for those deaths, because they both store their rockets and fire them from or near or under infirmaries and kindergartens and mosques. The most reasoned and eloquent argument that the best Israeli spokesman can proffer will always pale in comparison to televised images of Palestinians weeping over their dead.Experience shows that Israel will have time to continue the operation until one errant shell or bomb hits an apartment building or home and inadvertently kills a large number of people, or creates a heartbreaking reality, that will shake the world into action to stop Israel’s fire. And then Hamas, or whatever terrorist organization Israel is fighting at the time, will – too – stop its fire, until the next round.This happened during Operation Grapes of Wrath against Hezbollah in 1996, when more than 100 civilians were killed in Qana in southern Lebanon. It happened again in Operation Cast Lead in Gaza, when on January 16, 2009, a tank shell hit the Gaza home of Dr. Izzeldin Abuelaish, killing three of his daughters. Two days later the operation ended.And what is interesting about the international outcry in both those cases was that they took place when Israel was being led by a prime minister the world liked, and whom it thought was “serious about peace” – Shimon Peres in 1996, and Ehud Olmert in 2009.But now the situation is different.Now Israel has a prime minister not particularly enamored by the world, and who is not widely perceived as being a peace warrior. As a result, he has less credit in the world, and there is less global tolerance of his actions.Netanyahu obviously realizes all this, which is one of the reasons he likely waited as long as he did before launching a broad military campaign, even though the right wing of his coalition – as well as many of those living in the South – wanted to see an immediate, swift and painful response.Netanyahu needed international legitimacy for a fierce response, and that legitimacy would not have been forthcoming had he responded with the same power he is doing now, after the first, fifth, 10th, or even 100th rocket attack on Israel.But that legitimacy is not guaranteed forever. As the death toll on the other side climbs – regardless of the degree of havoc Hamas’s rockets are wreaking on Israeli life from Beersheba to Tel Aviv to Hadera – that legitimacy for firm action will narrow.Realization of this is likely one of the reasons Netanyahu and Ya’alon – both who have years of experience – have set relatively modest goals for the entire operation. They talk about “returning quiet to the South,” or “ensuring the security of the citizens of Israel.”One does not hear them talk about destroying Hamas, or knocking out its infrastructure and ridding it off all its rockets, as some leaders of the country did in 2006 prior to – and even in the first days of – the Second Lebanon War.Hurting Hamas, delivering a serious blow, harming its ability to operate; yes. Delivering a knock-out blow; no.Which is wise, because this country’s history of limited military operations teaches that the more moderate the goals, the better the chance of success.If you say you’re going to destroy Hezbollah, or Hamas, then if they succeed in firing one rocket a minute before the declaration of a cease-fire, they declare victory and get their victory photograph. To crush Hamas completely you need not only the will to commit ground forces, but also time to carry out the operation.And if the previous, similar operations in Lebanon and Gaza are any indication, the time Israel has to act is not open-ended.