I think you just explained why that wouldn't work. The UN is composed of its member countries. The conferences are held by representatives appointed from those countries. Those representatives will, in most cases, be representing the corporations who got their employer into power. For example, you may have noticed John Bolton, our former ambassador to the UN, is very keen on invading Iran as soon as possible. This works out nicely for companies that sell tanks, cruise missiles, guided bombs, etc. He was nominated into his position by George Bush. The Bush administration had initially planned to attack 7 countries in 5 years
, including Iran. When you start to notice all those no-big contracts going to Haliburton, and all the rest of the extreme overexpenditures on this war, it's pretty clear who Bush is loyal to, and Bolton was chosen by Bush, on behalf of those companies.
Now, if people like him are running all the UN meetings, they aren't going to be interested in helping the poor, unless they are representing companies who can skim some profit off of that. For the most part, they will only be interested in maintaining the status quo in order to maintain and expand the economic and political power of their respective corporations. The only competition between them will be the corporations in countries who get hit with sanctions because they're cutting into more powerful corporations' markets.
While there is no doubt that greed still seeps into the UN, the whole bit about defense contractors conspiring to push governments into war for the sake of profit is still more likely when nations act unilaterally. Less foreign support means more reliance on local military contractors. Furthermore, constant defiance of the UN means that there is less to stop a country from going to war in the first place.
The UN isn't exempt from corruption, but I see many of its other charter members as being much less corrupt than the USA, at least. If they were able to successfully defy the US and convince them not to attack nations, the defense contractors would definitely not get their way. As for socialized world charity, that may be an unrealistic dream, yes, but allowing foreign aid to become multilateral in nature is definitely possible, and would at least partially stop the predators.
The way I see it, the problem isn't necessarily free trade, it's a corporatist system that calls itself free trade, but could actually be considered neo-mercantilism. A big part of the problem is that governments act on behalf of monopolistic corporations, helping to spread them and squelch their competitors. After a point, it isn't even clear where a nation's fortune 500 companies end and its government begins, and the state acts as a monopolistic corporation.
Especially in the USA, we've almost regressed to hereditary aristocracy not unlike that of the Euporean monarchies of old. While a democracy on paper, the USA's political system is too easily bought out by the wealthiest political candidates, and the same so-called "first-families" of America have been able to offer such candidates ever since the USA was founded. The difference is that in modern America, wealth comes first, then helps people gain political position, rather than the reverse being true, but the end result is the same, and so is the ultimate cause: being born into a priviledged family.
So why my idea of multilateral aid to help fight this? Capitalism is based on greed, but at least in theory, the greed will be quelled somewhat if put at odds with greed from a competitor. Right now, foreign aid consists less of helping a country, and more of buying it out. However, if there were several equally-powerful nations invested in it at once, any invested nation that tries to gouge could be met with threats of striking deals with the competing nations. This would keep the investors more responsible to the people, in spite of their inherrant greed.
And what if it fails? Then the people should feel free to take up arms and take what they need themselves. But while I can see that happening in the third world, and even Europe, I doubt it will happen in the USA. I am not afraid to say this: I am incredibly dissapointed in my countrymen, and hope to move out of the USA as soon as possible. Hoping for a revolution is too optimistic; most of these fools don't even vote, and many who do can't do so wisely. Americans as a whole are compacent. And hell, if there ever actually was a successful people's revolution here, I'd be extremely skeptical of the American People's ability to govern themselves.