The 'fact' is irrelevent to Pollard's case. (But you have yet to provide the evidence or more importantly, a copy of the text of the alleged 'promise,' so it is hardly a 'fact.')
Here is why it is irrelevent: Pollard was not in a position to determine what the US was and was not obligated to do for Israel. Nor was he in a position to know how the information he sold was going to be used, or to whom it would be sold. Since he was not in a position to know any of these things, nor in a position of authority where he was empowered to make decisions on use of that information, he had no business appointing himself to be 'judge and jury.'
The next point is this: Pollard was a US citizen. If he holds a loyalty to Israel, he shouldn't have worked for the US or accepted a position in which his loyalties would be in conflict. He should have left the US and taken up residency in Israel, where he could in good faith swear loyalty to Israel.
But he didn't. He signed a contract and swore an oath in order to get his job with the USN. That oath was NOT to 'protect and serve Israel.'
Oaths are serious things- they are to be not to be broken. They don't have escape clauses; you are basically staking your entire being, your 'sacred honor,' to a cause by taking an oath before God. To preserve the sanctity of oaths, oath-breaking must be treated with utmost severity. Violating an oath is a voluntary act, as is taking an oath; there is never an excuse for those who break an oath.
Aside from the obvious immorality of betraying a free and trusting country, a country he had the choice of leaving, for the sake of another, and lying all along about where his loyalties were invested- the idea that he was doing something 'morally right' for the sake of a 'betrayed' Israel is totally ridiculous since he was paid (or bribed) to do it. He accepted money for the information he sold. If it was a great moral dilemma, he would have avoided accepting payment so as to keep what little integrity he had.
Some of the information Pollard sold to Israel had NOTHING to do with protecting Israel; some was the position of US ships. He may as well have threatened to murder every American on those ships, because he was certainly putting them in a position to be killed. He sold information on which USSR locations were our targets; he compromised US agents, endangering their lives. What he had was information that could be resold to any other nation and certainly used against us. His recourse if he really was in moral crisis was to look to law for a solution to his dilemma, or to quit as a matter of conscience if he could no longer work in good faith for the US.
Pollard willfully betrayed every sailor, soldier, and citizen of this country, put our security up for sale, and our lives as well. He did so knowing what he was doing, knowing the penalties for doing so, and has no reason to expect us to give him quarter. He recieved a light sentence. He should have been taken out and shot.
BTW, we could provide his last meal, I have this recipe for Cooked Goose, with.......