I disagree that Naval power is not a deciding factor.
Well Israel is essential an Island, on three sides it borders potential enemies and one side water. That water side must remain open for Israel to maintain supply (the old Sea Lanes of Communication thing again). Isreal has not fought a long protracted war, and would most likely not be able to without outside supply that supply must come by sea or be flown in over said sea.
The ISC is ill prepared to do much beyond coastal defense. It has only three large size corvettes and 8 older non stealthy missile boats. Its three submarines are generally used in the nuclear strike role (rumored anyways) and would be dangerous to risk them in direct combat (especially against superior Egyptian ASW forces). The ISC can't hope to break a distant blockade (a blockade far off shore) its few surface ships would be in danger of air attack and lack green/blue water ASW systems. The IAF has only three (outdated) Patrol Planes that are not designed for ASW focused operations. Also the ISC has no mine sweepers, one Romeo with a load of mines could shut down Israeli ports for quite a while.
The EN on the other hand has six frigates designed for blue water ASW operations and 7 frigates with basic ASW systems and 12 coastal ASW craft plus 16 ASW helicopters and 9 Naval Patrol choppers. They also have four old Romeo class subs that are equipped with decent torpedoes/missiles and received a sonar upgrade not to long ago. The ASW capablity of these is quite low but as an Anti-shipping platform they could be very dangerous if operated beyond the range of IAF/ISC ASW efforts (Say in the Strait of Sicily or the Malta Channel).
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