On the surface, concerns of symetry or "proportionality" in deaths “seem” reasonable so I thought I would write on this and put my views to rest with a (not TOO) comprehensive final word on my perspective:

What is going to satisfy the world? If one Israeli dies, are they, then, allowed to kill one Palestinian? Is it always 1-for-1? If the Palestinians lob, indiscriminately, rockets at population centres does that mean Israel may lob, indiscriminately, rockets at Palestinian population centres ... but mustn't hit anyone lest they kill more than they've lost (until, that is, one Israeli dies – where, then, they may, by dumb luck only of course, kill only one of their enemy)?

I heard a wonderful metaphore the other day upon which I would like to expand. Let's say there are two, armed crazy people at your door (two-armed crazy people might or might not be an entirely different thing) and they're banging on your door screaming they will come in and kill all your family. Do you want the police to send ... nobody because nobody got hurt (yet)? ... Or, perhaps they should send one officer to tell them to be quiet because you and your family can't sleep ... or do you want the police to send enough officers to make sure you are safe? And if the police come, what if they turn to the police, weapons in hand, saying, “We don't care. Our friends around the corner will come and finish the job.” What do you want the police to do?

And if they point their guns at your window, do you want the police to wait for them to shoot saying, “Well, they haven't shot at us yet and they haven't shot at you or your family or the building yet. We'll wait 'til someone gets hurt or killed. Then we'll act.”? (Of course, if they only hit your outside door – do you expect the police to go shoot their outside door?) What do you want them to do? And let's, then, say that one of your children and your spouse/significant other are killed so they kill those two ... or better yet, let's say they only succeed in shooting one of your family members (remember, we're only playing one-for-one here); do you want them to take out the one leaving the other shooting (remember, only one of your family died) do you want them to go back to their station ... and come back only if someone else gets shot ... or the criminals' friends around the corner come to you door? What do you want them to do?

The first obligation of any country is to protect its citizens. It's not a right. It's an obligation! Israel has that same obligation to her citizens. Just because we're Jews, our rights and obligations are no different. The specific mandate of Israel is to assure that what has happened to the Jewish people throughout history does not recur.
Read Article 51 of the United Nations charter

Just a little bit of (highly relevant) history - starting in the Common Era (leaving behind all pre-Common Era [BCE] events ... and there were enough):
The Roman invaders, in, roughly, 100 CE, renamed Judea (founded by Judah, the Lion of Israel – with Jerusalem as its capital) Palaestina. This was the first time the land was to be known as “Palestine”. The explicit purpose of renaming this land was to end Jewish identification with the land. Muhammad was, by the way, not even born yet. He was to come to life only 400+ years later. Islam itself, remember, was only to be established in, roughly, 600 CE.

Meanwhile, in 70 CE the Second Temple, built atop the First Temple (Solomon's Temple – on Temple Mount), was razed by the Romans leaving only the Western (Wailing) Wall. Today, Al Aqsa Mosque sits atop the second temple – overlooking what is widely believed to be the oldest Jewish cemetary and synagogue. It is noteworthy that Israel had not excavated for its historical site. Even under pressure, they have not attempted to excavate laterally (without damage to the mosque).

Under Roman rule, Jewish rebels gave and took their own lives on Masada – rather than being slaves again - this time to the Romans.

In, roughly, 1100 CE, while under rule of Richard I, England slaughtered all its Jews in York.

Between, approximately, 1350 and 1500 the Jews of Spain and Portugal were put to death. On the up-side, they had a chance to save themselves. They could “choose” to become true believers in Christianity. This way they would not become a victim of the on-going slaughter.

It was not until the 1920's that the term “Palestine” was, once again, officially applied to the region. That term, by the way, was applied by Imperialist England to all of what was known as Trans-Jordan which, today, includes Israel, Jordan and what may eventually be Palestine.

1933 – well, most of us know what happened. Well over 5 million Jewish victims have actually been named (for those of who think it wasn't in the millions ... or who choose to believe deniers, revisionists and minimizers).

Prior to 1948 it was the Jews (not the Arabs) who were commonly known as Palestinian. In fact, the term “Palestine” could not even be prounounced in their native language. They refered to the area as “Filastin”. The term “Palestine” was later co-opted to validate Arabic claims to all the lands.

In the time leading up to independence (1948) all of what is, today, Israel was actually Trans-Jordan. Trans-Jordan willingly ceded this land to the Jewish people. At this time, Jews were routinely stabbed on the streets of Jerusalem. No legal actions were ever taken. It was an accepted practice ... sport – as it was in pre-communist Russia and Ukraine.

Upon declaration of the provisional state, Israel was immediately under attack. The full list of combatants opposing Israel were: Egypt (along with forces lent to them by Saudi Arabia), Iraq, Transjordan, Syria, the Holy War Army (HWA), the Arab Liberation Army (ALA) and Lebanon.

The United States, as all other countries, stayed out of the conflict – help coming from individuals rather than states.

Arabs were not, in fact, exiled from their lands. They were encouraged by fellow Arabs to run through the spreading traditional blood libels and propoganda. The ploy was successful in turning Arabs against the new state of Israel.

1967 marked the Six Day War where knowing the forces being organized, Israel premptively attacked the significantly larger military forces of Egypt, Jordan, Syria and Iraq preparing to set upon Israel. Subsequently, in spite of this attack by many, more established foes, Israel Defence Forces (IDF) prevailed.

Then there was a war (of 20 days) where on the holiest holiday in Judaism, Egypt and Syria banded together again to attack Israel ... to squeeze her from both sides along with Jordan and Iraq (try #2). The attack was an undeclared, surprise attack on Judaism's highest holiday of the year when most troops were home with their families – Israel simply not believing that anyone would attack them knowing of this holy day took a beating. We all know the result. Ultimately, Egypt capitulated having lost a hunk of the Sinai and Syria who kept fighting on lost the Golan Heights.

Eventually Egypt signed a peace treaty with Israel (for which, it is widely believed, Sadat was assassinated). Israel (as they always said they would) traded land for peace. They gave back the Sinai and good to their word, the never lifted a finger against their new friends – Egypt. King Hussein flew his own jet to a meeting with then Prime Minister Golda Meir where they signed a peace treaty. There have been no new hostilities between these two friends. King Hussein, mind you, had come under attack (even before the signing) from “Palestinians” militants camped in Jordan – escaping, barely, with his life.

Of course there have been enough other wars from Israel's short history. There have been enough terrorist attacks on civilians (suicide bombings, indiscriminate rocket fire, attacks on civilian planes and cruise ships – with the specific and sole intent of killing Jews – whether they are Israeli or not). While Israel and Israelis hardly do everything right (there are good Jews and bad Jews just as there are good Muslims and bad Muslims) I won't stand against the state.

Fact is, it is “only” the Jewish people have had a constant presence in that land since biblical times.

Today we say, “Never again!” We will never willingly let another shed our blood and we will not silently accept blood libels that drove anti-semetic and anti-Israeli thinking. Israel is there, specifically, to make sure that “never again” means “never again”.

Ask any IDF member – Masada shall never fall again!

While this is essentially factually correct there may be some minor technical errors ... but it is, essentially, factually correct.