Yes.
Are you sure? As a naturalized citizen, I will never forget the words of the oath I took: "I hereby declare, on oath, that I absolutely and entirely renounce and abjure all allegiance and fidelity to any foreign prince, potentate, state, or sovereignty, of whom or which I have heretofore been a subject or citizen;
I don't know what this means to you, but to me it means that I gave up my Spanish citizenship the day I became an American.