I really don't understand why Loudoun was shocked that the "leading people" in the colonies defended their "Liberties" and opposed "royal authority?" ( I really need improvement in my History subjects.)

Basically, all those who advocated "liberties" and defied the British were committing treason. That's why the last paragraph of the Declaration of Independence is so important, and the very last part is quite startling if you are aware of what would have happened had they lost the revolution.

http://www.ushistory.org/declaration/document/
"And for the support of this Declaration, with a firm reliance on the protection of Divine Providence, we mutually pledge to each other our Lives, our Fortunes and our sacred Honor."

=)