Permanent Interests?

Let's see, since the mid 1970's:

 

Iran has been a friend of the US and then an enemy of the US

Iraq was a foe (Soviet Satellite), then an ally against Iran, and then a foe once more.

Early on in the Iran-Iraq war, the Iranians bought spare parts for is military from Israel, its enemy.

 

All the while, black America has never wavered in its support of the democratic party. What kind of sense does that make?