I never said so. But the voting for a Mormon does logically prompt questions about what are the outer limits of litmus-test politics.
For conservatives, I the litmus test would first and foremost be agreement on the preponderance of basic values, such as life, liberty, a nation whose laws are derived from God and not from government. There would also have to be the basic belief for Americans that their country is worth preserving and would not be better off if sharia were to be the law of the land, for the Judeo-Christian values upon which America in particular was founded are incompatible with sharia and other such systems.
Then, more specifically, for conservatives, would be a belief in smaller government, and investing as much power as possible in the individual, and the belief that we are the ones most capable and most responsible for making the decisions in our own lives.
In a pluralistic society, where freedom of religion means that people differ on many religious tenants, such as whether the Eucharist should be taken on the tongue or the hand, whether Jesus is the son of God, or even existed, whether Mohammed is a prophet of something entirely different—all these are questions of faith and theology. They inform religious values, to be sure, but in terms of natural law that Catholicism expects from all of humanity, different religions ought to come to the same conclusions on many things, as long as logic and reason and rational thought are guiding the ethics of us all.
Catholics such as Pelosi who have strayed from the American value of life follow neither natural law or Catholic teaching. They have failed the litmus test. Many Mormons and Muslims would therefore be preferable.