It's not so much that they're preventing their enemies from having firearms, they prevent mostly anyone non-Jewish who hasn't served in the IDF (or who is not a "settler") from being allowed to have one. Even for "allowed" Jewish Israeli citizens, the firearms are not a right, they're a privilege and one that can be quickly revoked. Our Israeli guide explained that the government would let you check out an M16 from the police in order to escort a school's field trip, but that was only because the .gov decided the M16 was needed for protection, and you had to return it to the police when the trip, and therefore the "need" for the gun, were done with.
That said, I enjoyed my visit to Israel and felt safest from attack when amongst a throng of soldiers/citizens carrying dozens of long guns and handguns. Were you to be allowed to immigrate, though, you could probably just forget about getting a permit for any kind of firearm.