Yes, it matters to me if the President of the United States is a moral person, because the President is supposed to be a leader in politics, as well as set an example for the country in behavior. If the President does not go to church on Christmas, other people think they should not go to church on Christmas. The President sets an example.
It matters much to me if the person of president of the united states is a moral person. His ability to differentiates rights from wrong and his will to pursue with vigor what he considered right is important for justice and equity to prevailed in the society. It is also vital for policy formulations and the implementation process as well as foreign relations.