What is political creed

A creed is a difficult concept to explain.
To put it simply, a creed is a statement of belief. It is usually a single phrase that sums up what every member of your order must believe in. For instance, the Assassin Order's creed would be,
"Nothing is true. Everything is permitted."

A political creed, in that sense, would be the same thing, but it would describe something about government or nations. The American Creed is an example of a political creed, of which is:
"I believe in the United States of America, as a government of the people, by the people, for the people; whose just powers are derived from the consent of the governed..." it goes on from there, but I think you get the point.