The Nature of LDS Belief
If Mormonism may be called Protestant or Christian, it would have be done so very loosely. Mormons emphatically belief in the contrariety of the Church Catholic and properly Protestant to the actual truth. PBS reports "These key elements of the faith include belief in God the Father, his Son Jesus Christ and the Holy Spirit; belief in modern prophets and continuing revelation; belief that through Christ's atonement all mankind may be saved by obedience to the laws and ordinances of Christ's Gospel; belief in the importance of repentance and baptism by immersion for the forgiveness of sins; and belief in the right of all people to worship God as they please. The Articles of Faith also affirm a belief in the Bible as the word of God, insofar as it is correctly translated, and in the Book of Mormon as an equally important scriptural source."
On the surface it feels like Christianity, however, in its more fundamental belief it ceases to be monotheistic and without the possibility of preventing cultural corruption. Mormonism may be a step behind the culture on most things, but the is only elders to keep it from lauding the same evil as contemporary society. This may be understood as a rest refutation, because there is no mechanism by which authority guides its followers from the creativity of the "prophets" which every believer is for this religion. This is perhaps the most fundamental critique that can be offered, because as it relates to the rest of Christianity it can only claim we are deceived and that is a proposition one can see is not true, but it is not actually possible to prove we are not deceived. As the rest of Christianity relates in return is in like manner, because its claims are so bold and contrary to any historical scripture scholarship an argument can scarcely be made. Even the statement quoted above, as similar to Christianity as it seems, presents conclusion without the minutia of their practice and logic which do not bear congruence with traditional Christian faith. This religious defect results from its very beginning with Joesph Smith whose name is mentioned 173 times in the Doctrine and Covenants "book" and "Jesus" only when the name of the Church is mentioned. The premises for their tenets of faith come not from Scripture that predates Joesph Smith but Joesph Smith themselves. This is to say Neither Scripture nor History is their authority but the "latter Day" "prophets".
If you have further curiosity on the subject, click here to read PBS on the subject.