Study the history of Utah, it is fascinating. The US Army was used to force the LDS to change it's stated theology before Utah was allowed into the Union. They had to make polygamy forbidden by state constitution. Think about that for a moment. The law and the LDS has an interesting history.
The Mormons then were a bunch of American rebels who has illegally seized US territory and were pretending to govern it as a sovereign entity against US Laws under the shade of a recently invented religion of convenience. What could you possibly expect except for the US Army to come in and enforce US claims and statutes???