Wars are inevitable under the capitalist system run by the banks and corporations. We make tons of stuff then destroy it all in war so we can then make tons more. It's a bit like the slash and burn approach to farming. This rolling process ensures that the rich get ever richer and the numbers of poor people are kept within manageable parameters.
If you want to put a stop to this process - and who wouldn't (unless you're a banker of course) - then push for the adoption of direct democracy: a system of government wherein the electorate directly enact laws for themselves. This system doesn't require politicians or 'leaders'.
Without 'leaders' to 'lead' us into wars: usually by telling us lies - just as they are doing now about Iran - there will be no more wars. There will be no more poverty either.
So get with the program.