Yes, they do that a lot. Egypt, Lebanon, Jordan and Syria in 1947, Egypt Jordan and Syria in 1967, Egypt, USSR, Jordan, Syria and the PLO in 1967-1970 and Egypt and Syria on Yom Kippur in 1973. Suez in 1956 did have Britain and France with with Israel against Egypt for the Suez canal.
I doubt very much Israel is looking to start a war with Iran. If anything, these actions are meant to remind Iran that a war with Israel would come at a very high price. And yes, I expect the west will stand with Israel if push comes to shove.
No.
An air war, fought with rockets and planes, is possible, though - and may well be what Netanyahu’s angling for here.
If it’s short and decisive, he’ll look good; if it’s protracted and messy, he’ll look bad.
But I doubt a war, by and in itself, will really change much of anything except Netanyahu’s re-election chances. Even if Israel “wins,” Hezbollah will still be around, Assad ain’t going nowhere, and bombs alone won’t topple the Ayatollahs. And even if Israel “loses,” it won’t lose an inch of land, just pride and prestige.