In fact, we could probably feed about twice as many. Energy and fuel scarcity aren't the problem either. The problem is that the earth has a limited capacity to absorb the heat, effluent, and waste that come from energy consumption. Long before we run out of oil or coal or solar energy, we will run out of fresh air, clean water and a survivable environment. Engels wrote that you can do what you want to nature, but nature will have her revenge.
Population is a factor.
The poor have a lot of children because they are poor and children become a source of social security and all that. His accomplishments are formidable. He has destroyed the public economy. He is loyal to the concept of total privatization and corporate investment. He used force and violence in 1993 to kill over a thousand people who were defending parliament.