The 1967 crisis escalated from a boundary dispute into an existential confrontation

Evidence

For the Russians and Arabs, the crisis began with an Israeli invasion threat against Syria—which the Israelis said was non-existent; for the Israelis, it began with Egyptian troop concentrations in Sinai and the blockade of the Straits of Tiran—which the Egyptians said was lawful. Politicians and historians will argue for a long time to come about what really happened, and about the guilt, com­ plicity, stupidity or innocence of those involved. But as the tension mounted, in late May, the arguments about fact and law became increasingly irrelevant. What­ ever the causes, whoever the authors of the crisis, it soon became clear to par­ ticipants and observers alike that the question at issue was no longer a border or a blockade, but the whole problem of Arab-Israel relations. — Bernard Lewis, From Babel to Dragomans, 1217