"Tis of Thee" we sing, but who's the "Thee"?

Attending a Protestant church in America on the Sunday around the 4th of July might be hazardous to your spiritual health.

Under what reasonable understanding of the Christian faith is it ok to sing "My Country, Tis of Thee" in a Sunday morning worship service? I thought the "Thee" we were supposed to be singing to was Jesus.

Would it make any sense for me to sing a love song to my girlfriend in church? Most people would find that very inappropriate. Not that they would be opposed to me loving my girlfriend or singing a song to her. Nor would God. Human affection for one another is good. However, when the focus is supposed to be on our Creator and Savior, it doesn't make any sense.

I think patriotism is like that. It's good, but it's not what Christianity is about. Ceasar might be important, but Jesus is Lord.

Am I wrong about this?