"Wherefore, men are free according to the flesh; and call things are given them which are expedient unto man. And they are free to choose liberty and eternal life, through the great Mediator of all men, or to choose captivity and death, according to the captivity and power of the devil." - 2 Nephi 2:27
The Constitution Guarantees Agency & Liberty
Many of the founders of our country (especially of the Jefferson/Madison crowd) believe that as God is eternally free and we are created in his likeness & image, we too, are eternally free. We are guaranteed life, liberty, & the pursuit of happiness in the Constitution.
We have the freedom to choose good and the freedom to choose evil insomuch as that evil does not infringe on the rights of others.
Many are Choosing Satan's Plan
Since the time of the constitution we as a nation made up of the natural man have moved into the tyrannical state of forcing others to do what we think/believe/know to be right and good.
This is happening on the Left and the Right. It is a Democrat problem and it is a Republican problem.
For example:
The Left wants the freedom to put whatever they want in their lungs, but they don't think someone should have the freedom to do what they wish with their money.
The Right wants freedom to do with their money whatever they wish, but they want to force you to not put drugs into your body.
My libertarian argument is that we don't force other to do what we know to be right or correct. Let's not confuse the role of society and churches with the role of government. Society should urge each other to do good and be righteous. Government should guarantee our freedoms.