I won't take a position on that because I don't honestly know which way would be better. However, I am confident that with emerging technologies, we can better sustain the growing Earth populus and reduce our impact on it - renewable energies are emerging, products are being more compostable, better systems for farming, etc. If we had 6 billion people living on earth in the 1920's, we'd have a problem as technology for food growth, mass transport of goods, more efficient energy solutions didn't exist or only partially existed.
The fact that you assert that the best way for the Earth to continue on is to kill off a couple billion people is truly, in my opinion, the stupidest thing I've ever read. And if you think that chemical and biological weapons wouldn't have impacts on the environment either, then that is just as bad as well.
And for the record, your comments make you out to support genocide because billions aren't going to die if we just stopped giving aid.
As for the imploding of countries, it's a natural occurence through history. If the economy keeps up as it is, we could see some completely collapse within a few years.