Without US or UK air support, the IDF airforce is in disadvantage. The US has airbases almost in every neighbouring country.
But for the IDF the distance alone is far to great to bomb the Iranian cities or facilities and fly back home unharmed.
Every time the Israeli airforce leave their hangars and fly to their targets, Iran can launch a great salvo of rockets to Israel, and this time with bigger warheads.
It's a lose-lose situation.
Other middle-eastern countries have co-operated with Israel on airspace considerations a bunch of time for one, and for another (far more pertinent) point the U.S. and UK aren't going anywhere in terms of support. Not now, not ever. It'd take Israel setting off nukes, and only way that happens if if they're literally overrun with Iranians and Syrians and Lebanese in Tel Aviv by the tens of thousands. It ain't happening.
Another point: Israel's hit Iran from the air before, without the U.S. It's a tricky long-distance exercise, and the more planes you have in the air the more chance you're getting seen on the way, but it's not impossible. Not even with 15s and 16s - they've done it before - and if you can launch 35's from friendly location outside Israel & closer to Iran (again, a challenge, not impossible), Iran's not going to have a good day. SAM sites are great and all, and Iran's up there in capability with them, but they're hardly impenetrable.
Also see you're not going to follow up with the whole "derpa derpa Iran's on the level and honest when they say they took out dozens of F-35s!", too. There's jack-shit supporting that, bar a photo of destruction of a non-armored/fortified hangar, which isn't where Israel stores high-end airframes anyway. You're in Ghost Of Kiev propaganda territory with this crap.
EDIT: Also, since I'm sick of reading it, I'm just going to go all "Scott" here, lowest-common-denominator of discourse. Dozens more Shia Orcs atomized today by the Chosen People, ROFLWAFFLES. Etc. Since, you know, that stuff's okay on this site evidently.
