What is a political principle?

A political principle is a general normative rule about how political power, rights, institutions, or public decisions ought to be organized or exercised.

Examples:

• Citizens should be equal before the law.
• Governments should protect minority rights.
• Sovereignty belongs to the people.
• Present stewardship should outweigh ancient occupancy.

Notice these are not historical descriptions.

History asks:

What happened?

Political philosophy asks:

What should governments do?

That is why "present stewardship should matter more than ancient occupation" is a political principle rather than a rule of historical method.