In spite of a growing population, farm land in the USA is declining. "In 1990, there were almost 987 million acres in farms in the U.S., that number was reduced to just under 943 million acres by 2000, and then reduced to 914 million acres in 2012." http://www.epa.gov/agriculture/ag101/landuse.html
The major problem, of course, is interfering with people's lifestyles, if only in marginal ways... we as first-world countries just don't handle having our convenience messed with very well.
First of all, just because food isn't used doesn't mean it is wasted. I don't like to go to the store all the time so I buy more food than I may end up using -- but I still consider it worth it.
Second there is not an limited amount of food in the world and there is no reason we have to cut down on our use in order to feed hungry Africans -- we can, as GP correctly pointed out -- feed the entire world.
At this point the only reason there is hunger anywhere in the world is bad governments and failed states -- Haiti is hell on earth (and has been before the recent earthquake), but it borders the Dominican republic, which is much better (if still far from the western world), NK is the worst place on earth with street urchins scavenging for single kernels of rice in animal dung, SK, which it borders, is a pretty good place to live and has basically no starvation.
It is one country today, but the same difference (albit to a lesser degree) could be seen between East and West Germany.
Finally, take the recent hunger situation in Africa -- people had to walk miles through the desert, leaving their dead and dying children behind in the sand because they couldn't carry them. They had to walk until they came out of Somalia and entered Kenya where they would receive held and food -- because the warlords of Somalia didn't allow the food aid into the country as they believed it was a western emperialist attempt to make Islam look bad.
Yes
and getting it to people who need it.
Not so sure about this one. Fostering dependence and quite simply the costs of airlifting tons of produce and bread to North Korea on the regular come to mind.
I do not think a lifestyle change is required on the Western world's part, this all about politics. Even when disasters strike not all aid is accepted and it is either purely political or with religious overtones.
What is to be done with the countries that through corruption, incompetence, or malice prevent food aid from reaching their citizens? What exactly is the developed man's burden, here?
This is a tricky point.
We already grow more than enough food, and have for a long time: http://en.wikipedia.org/wiki/Food_waste
Economic innovations won't help with that, but engineering ones might.
Or just remove the trade barriers with Africa and start buying from them like we do with the Chinese.
But i've seen better solutions to this problem .one example is letting bacteria grow basic food elements at 10x less cost, like pronutria claims.another example is making high quality chicken substitute from soybean,which,depending on proces could be much cheaper than chicken.