why did it took several centuries before the civilizations of the two hemispheres had communication??

Due to lack of technology.

Explanation:

It took several centuries before the civilizations of the two hemispheres had communication because of lack of technologies that can make a bridge of communication between two hemisphere. People are not interested in research and having old wrong beliefs that prevent them from growth and development but due to renaissance movement people get rid of false and wrong beliefs and work for the advancement of technology which leads to communication between two hemisphere.

in this part of the declaration it refers to the point when american people didn't recognize the british domain and   breaks the political bands with britain, they forced a respectful separation.

mankind was created and entitled equally with rights   which were life, freedom and the seeking for happiness.

answer; /// more likely to fight in the future;