Israel's 1967 attacks were justified as necessary self-protective strikes against Arab forces allegedly massed to invade them on three borders. In truth, Israel was worried that Nasser represented a strong potential leader who might unite the Arab world against them and wanted to eliminate him as a leadership figure. Egypt's closure to Israeli shipping of the little-used Straights of Tiran was seized upon as a provocation, which had been an inconsequential gesture in response to Israeli belligerance in Jordan and Syria. This permitted Israel to claim Egypt to be the primary threat against which a pre-emptive strike was justified, although military analysts including Chief of Staff Yitzak Rabin had informed the Israeli Cabinet just weeks before their attack that Egypt had no invasion force in the Sinai. Years later Menachim Begin publicly acknowledged that their claimed threat was falsified. "We must be honest with ourselves," Begin said. "We decided to attack him."
Israel also attacked Jordan, on the pretext of punishment for the pragmatic King Hussein's failure to fully prevent Palestinian infiltration into Israel where they committed occasional acts of terrorism despite Jordan's best efforts to prevent this. The Israeli assault resulted in seizure of the entire West Bank that they had ceded to the Arab Legion in 1948 in exchange for the Legion's non-interference in the original Zionist ethnic cleansing.
Israel also concealed their intent to attack Syria, culminating years of progressive encroachment upon Syrian land, sporadic retaliation for which was used to justify their invasion. This was in defiance of explicit US wishes, largely in order to secure the Golan Heights water supply.
This 6-day blitzkreig by the IDF displayed Israel's consistent MO:
 drive people off their land and seize or destroy their homes;
 call them "terrorists" when they retaliate or attempt to regain their properties, and then attack them with ruthless brutality (see Israeli massacres);
 provoke neighboring governments to defend the victims of these raids within their territory;
 use these defensive reactions as a casus belli should Israel perceive something to be gained by armed hostilities;
 always loudly proclaim the morally impregnable role of victim, however inconsistent with the truth; and
 invent a mythic network of disinformation about these events to propagate within their own population and throughout much of the world - especially the United States, whose support and indulgence they desperately need, facilitated by an elaborate, well-funded and well-organized lobby and coordinated social network maintained for that purpose in the US.
Altogether, Israel has engaged in 20 wars during its 60 years of existence, 19 of which it has started. Only in 1973 was Israel attacked first, and that was only to regain Arab lands stolen by Israel in 1967 and their forces did not violate the internationally recognized borders of Israel. The relentless belligerance of Israel has kept the area in turmoil throughout its short history. Secretary of State George Marshall had warned President Truman against recognizing Israel in 1948, envisioning nothing but trouble ahead if he did. He has been proved prescient.
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