I think it’s about the enemy soldiers starving into surrender, not the civilian populace.
Shy of magic, that's not a policy you can implement. Either people in a region have access to food or they don't. You can't just put a stamp on a loaf of bread that makes it inedible to anyone carrying a gun.
Are UN resolutions like patents, where only a small fraction of the text is actually meaningful?
:-/
A lot of it is legalese that matters much more to an actual court system than a random layman picking through the fine print. But yes, broadly speaking a central critique of the UN has been its habit of going out and announcing "Bad Thing Is Bad" and then failing to do much to back that statement up.
At the same time, when the UN has intervened... well... look at the horror show that was the Korean War. Nevermind the intervention and occupation of Yugoslavia or Somalia. Or the Oil for Food Scandal with regard to Iraq.
I mean, the fundamental problem with the UN is that its still composed of many of the countries that are actively participating or tangentially benefiting in whatever horrible thing they're supposed to be preventing. Much like any republican institution, you're stuck with people who were put there by the corrupt institutions they're supposed to police. How do you untangle that web? Ask Alexander the Great, maybe.