Final answer:
Congress was intentionally created to act as a check on the power of a single leader and to maintain freedom for the American people.
Step-by-step explanation:
The specific purpose or design principle that Congress was intentionally created with in mind was to act as a check on the power of a single leader and to maintain freedom for the American people. Congress serves as an independent legislature made up of representatives of the people, which is a key test of freedom in any country. Its historic mission has been to maintain freedom by being a counterbalance to executive power.