Yorktown is on a peninsula, facing the York River. The Continental military did not have the naval power to block the British Navy from entering Chesapeake Bay and providing support, ie. bombardment of US positions, and reinforcements, or if necessary, evacuation of British troops.
The only way that Washington and his generals could trap the British Army and force the surrender was through the help of the French Navy, who DID prevent the British Navy from entering the Bay and providing that support. French land troops bolstered the Continental Army as well, but it was the Naval support that truly turned the tide and made surrender the only option for Lord Cornwallis and his British
There is always an abundance of natural resources for the different begins inside a region, and they too are very precious or we can say valuable because most of these sources if existed may turn very badly for more the just one individual. While, our planet is considered to be the only habitable place inside this universe to live for all the living beings, just because we have a lot to lose if we do not get enough of these vital natural resources required for our survival.
So, for more then thousand centuries human have evolved itself as according to its need and for that there are have been very few times when we experienced lack of products important for our survival.However, due to high high number of individuals inside the civilizations there are certain precautions taken by the international communities in order to limit our as according to the natural resources present for our survival. Because, human body is much complex and evolved then ever and for that reason we can live inside such an environment where the natural resources are much less then always.
