Correct.
... and eligible to be President.
His parents were not citizens when he was born. Therefore, he is not a natural-born citizen. If you do not think the Constitution means anything, then LEAVE the US. My ancestors fought and DIED for the Constitution, and while I draw a breath, I will fight to move this country back to that sacred document.
My ancestors also fought in the Revolutionary War: it isn’t a rare distinction.
Please quote exactly the part of the Constitution which you contend disqualifies Rubio in view of the fact that he was born in the United States.