In all fulminant crises between the enemies in Near East I always sided with Israel, in 1967 my first staggering into politics were leaflets in the school to support the Israelian troops against their Arab Enemies. With the exception of my maoist deviation in the 70th, this has never changed.
There are deep reasons for this, rational ones and irrational one. Among the irrational is my admiration for the jewish culture and especially the secular products of the jewish culture, admittedly also my feeling guilty as a German. Later on about the rational reasons. This time, when Israelian ground troups invaded the Gaza strip I was to change position and to condemn equally both, the Israelians and Hamas Palestinians. I thought Israel finally has lost any realistic view on what is called in German "die Verhaeltnismaessigkeit der Mittel" (somewhat like ddisproportinate response).
Then when I saw the peace demonstrations in Milan, where adult idiots sent children with posters on which where shown Solomon-s seal together with the swastika. Israelian flags were burnt and Hamas flags were displayed, I changed quickly position. I am supporting Israel! I do not share the strategy, but it is self-defence against a continuous attack against the jewish state. As some one on the left wing of the political spectrum I will continue to elaborate on this to hinder that any justified criticism of Israelian politics is abused to justify terrorism and the murderous policy of despotic arab/iranian and palestinian leaders.
To evidence the bias in the European left I want to cite from the Blog of Stephen Law (https://stephenlaw.blogspot.com/2009/01/bit-more-on-israel-innocent-victi...), a British philosopher which I esteem very highly.
Stephen writes: "Suppose that after a few IRA attacks leaving 11 Brits dead, the British Government invaded Catholic areas of Northern Ireland with tanks and air strikes, seeking out IRA members and arms caches, but killing over a thousand innocent Catholic by-standers in the process." This is unfortunately a wrong comparison. The comparison would have been true, when the IRA would have been elected by a large majority of Northern Ireland citizens and would have declared as their goal to eliminate all protestant inhabitants from Northern Ireland. I can imagine that the reaction of the British government would have been at least as bold as in the case of the Falklands. There are very few innocent bystanders. The Palestinians in the Gaza stripe are responsible for the Hamas government as the Germans were for the Nazi Government.
There is a deep refusal in the Western left to look to the details and the history of the conflict between Israel andits Arab neighbours, the Palestinians in particular. (There is an exellent article in the last economist - https://www.economist.com/opinion/displaystory.cfm?story_id=12899483&fsrc... -)
You may argue about the decision of the United Nations to divide Palestine between Jews and Arabs, but it was a bipartisan decision by the communists and the West, not shared only by the arab states. This decision was acknowledging mainly facts. There were 600,000 Jews in Palestine and about 1.8 Million Arabs and the most pragmatic decision seemed to divide the country. The division was accepted by the Jews, but combated by the Arabs, who went to war and lost.The Palestinians had many opportunities for getting their own state. They shunned them. "Abba Eban, an Israeli foreign minister, quipped that the Palestinians “never missed an opportunity to miss an opportunity”. Israel’s story is that the Arabs have muffed at least four chances to have a Palestinian state. They could have said yes to partition in 1947. They could have made peace after the war of 1947-48. They had another chance after Israel routed its neighbours in 1967 (“We are just waiting for a telephone call,” said Moshe Dayan, Israel’s hero of that war). They had yet another in 2000 when Ehud Barak, now Israel’s defence minister and then its prime minister, offered the Palestinians a state at Bill Clinton’s fateful summit at Camp David." (from the Economist article) Only in 1988 the PLO under Arafat renounced its goal to destroy Israle and to drive all Jews into the sea. Hamas is still insisting on this, backed by islamic fundamentalist like the Iranian president.
Israel is still combating for its survival.

Having said this I still consider the israelian action now politically wrong and disproportionate. Israel will never get peace, if they go not back to the Camp David agreement, concede a Palestinian state with all of the West Banks and the Gaza Strip- and with Israel in the boundaries of 1967. This will need multiple international guarantees to avoid that the new palestinian state will become not only a deployment place of islamic terrorism. But there are no alternatives. Israel needs to dare, but as more burning israelian flags they will see on our side and Hamas flags in bella vista, as less they will be willing to risk.