Since they control lots of island groups which makes thing hard to border up and defend on all sides... Unlike in Germany which they had 2 fronts and it was easier to have bunkers to defend certain location...
Answer:
By issuing the Declaration of Independence, adopted by the Continental Congress on July 4, 1776, the 13 American colonies severed their political connections to Great Britain. The Declaration summarized the colonists' motivations for seeking independence.