The UN has the power but will never use it. Its not in there interest.
Cutting off the USA from the rest of the wold will do it. No cars, bikes, oil, wood, consumer goods nothing in or out. That will stop the US citizen from thing war is a good thing. The UN can hunt down and ....... remove the leadership of any "rogue state". But do that to the USA? who is going to pay for or suply the troops for there next "intervention"

As far as the Israel VS. Palestine. As I see it there the same place just with different people in it. (dam sillyer still ther the same God probly related to each other) Israel was there then Rome came renamed it and ran off many of the Jews then Rome fell, WWII came about and Israel was made they had a war and claimed some of "their" land back. But not all of the land they wanted now here we are. If the USA stops bank rolling this it wont stop.

Oh there is Palestine blowing up people and Israel dong the same right back (or was Israel the ones who shot first). But in the end like all dam silly kill them all wars there leadership is who is to blame. There greed, self importance, holier than thou, and what must just piss off the BIG guy "God told me to".
And yes the US will end up paying 10x the price to fix the place up rightfully so I think to bad it wont be the people that helped it to happen.
The leadership sits around getting fat and rich while the poor are killed. I think there is a big table some place there all the rich and powerful sit around and plot how to get richer and more powerful. The lives of people are set at price as are all the weapons that are used. The Price is calculated out and deals are done the press is told where to go and what to say. The lives of the poor don't matter to them and never will.

No making the poor tax payer pay for a war is not going stop pointless wars. But holding the leadership of the nation invading at gun point and shooting some of them on TV and on ytube will. Trying them for war crimes will.

Most people in a war don't care about who flys what flag they just want live there lives. At one point Israel and Palestine worked side by side lived at pece in the same street and even had kids together. But some little man with his little mind and huge ego beat the drums of patriotism (or religon or race) to make his pupits dance and they did.

But do you want the UN as dictator? If the UN said to Argentina you are going to war will you? Argentina is the 23 largest economy in the world and sat out WWI and WWII. If the need arises will Argentina go to war spending its money to defend places richer than it? with little pay back? will it rebuild places that have had it better off than it?
Till the wold has a resounding yes then no this idea will not work.
To bad to GRATE idea.
Then so dose not spending $ on war but helping out build up infrastructure. With half the price of the war spent on realy helping people ot with a road or two and some wells and maby power and go realy nuts and a tin and brik homes and seeds and chikens and a goat. there will little need for war. Gust think all that junk the US throws out but is sill good, drop that stuff out side of citys and towns in places that are mad at the USA how can you stay mad at a people that gives you all that. We did that with food in more than one place and got better results than shooting at them.

I will take 2 stickers.