you're using the term "liberty" as if it is a unconditional right with no boundaries. surely you must acknowledge that total liberty, total freedom cannot exist when a nation of 350 million individuals want to thrive, advance, and to defend themselves against exterior threats. in the course of those pursuits for the common good, nearly all individuals are going to be required to make some involuntary sacrifices. Every law is a restriction on liberty and freedom of the people whom left to their own devices, would act conversely. but I think you would agree they are required for our nation to endure.
if we agree (and perhaps we don't) that at least some limits to individual liberty and freedom are required for a nation to function, then we only disagree on where the limits are placed, and that's subjective. You can't just point to the Constitution and say it contains the word "liberty". what we seek is a nation that provides the MOST individual freedom and liberty for the most people while still ensuring the nation as a whole continues to succeed.
since the time period immediately after 9/11, i believe we're seeing a breakdown of our national values and our national identity. a thing i've learned from my military service is that overall, the connection in values and identity I shared with my military coworkers far exceeds anything i've ever seen outside the military. Why? because we share common experiences, adversities. the amount of personal sacrifice for something dictates the value you place on it. I think it is no coincidence that we are seeing a decline in appreciation for our nation as we're also seeing a decline in the rate of voluntary military participation (sacrifice).
I will say i do not believe in "serve or prison" in most cases, but I think compulsory national service could be heavily incentivized, and it need not be military. Our security and prosperity was earned through a great deal of sacrifice and a great deal will be necessary to maintain it. A lot of work needs to be done and if you want to enjoy all the great aspects here, you should be required to do more than simply exist. all the free-loading libertarians should be required to do their part.