Hobbes thought that individuals agreed to the establishment of a government in order to uphold the law and prevent the anarchy of the natural world. The preamble of the United States Constitution states that "We the People" established a government to "ensure domestic tranquility" and "advance the general good," among other things.
Hobbes believed that to enforce law and prevent the chaos of the state of nature, people consented to forming a government. This idea is written into the preamble of the U.S. Constitution, when "We the People" establish a government to do things like "ensure domestic tranquility" and "promote the general welfare.
Yes, I think it was because you need to remember that they wanted to ultimately be joined to the U.S. By incorporating ideas from the U.S. Constitution, it would be a much easier integration into the U.S.