Oh how I agree with your "profound sadness" that Romney felt it politically necessary, in 2007, to give a speech defending his right, as a Mormon, to run for the presidency. After all, over 210 years ago, in the early years of our country George Washington confronted that issue and dismissed it in writing:
It is now no more that toleration is spoken of as if it was the indulgence of one class of people that another enjoyed the exercise of their inherent natural rights. For happily, the government of the United States, which gives to bigotry no sanction, to persecution no assistance, requires only that they who live under its protection should demean themselves as good citizens, in giving it on all occasions their effectual support.
Washington was replying to a Jewish citizen in Newport, RI, Moses Sexias, who welcomed Washington when he visited the city. That answer should have firmly settled the non question; Al Smith, John F. Kennedy, Joseph Lieberman, Mitt Romney and who knows who else was discouraged, should not have had to defend their personal religious beliefs or apologize for their gender or ethnicity.