The slippery slope may be a logical fallacy, but the ratchet effect of government growth is historical fact. Here in the USA, we claim to be the "land of the free" and the "home of the brave," yet somehow we have the highest incarceration rate in the world, and almost everything is illegal. What isn't completely forbidden requires licenses, permits, taxes, registration, documentation, and every other form of authoritarian oversight possible.
We have transformed into a society where the acquisition of a driver's license is seen a rite of passage toward adulthood, and not an unconscionable imposition from an unaccountable government monopoly. Of course no one wants reckless, ignorant motorists on the road, but if we look at the matter honestly, the government license racket does nothing to really prevent this. Unlicensed drivers are everywhere. People drive recklessly. People ignore pedestrians in crosswalks and blow through stop signs and traffic lights all the time. The "solution" is the threat of a fine, property confiscation, and possibly incarceration. The crimes of theft and kidnapping, if we speak honestly. And these crimes are often inflicted on people who have committed no real crimes themselves. No papers? Punishment. Not registered? Punishment. Unapproved modifications? Punishment.
In the wake of the Virginia gun rights protests, the mealy-mouthed apologists for more government control insist that their intentions are so virtuous that questioning them is tantamount to advocating violence. "We just want to register dangerous objects for your SAAAAFFFFFETYYYY." So benevolent. Never mind that these always include the threat of very real violence against anyone who does not comply. "Just do as you're told" isn't liberty, but it is twisted by sophists pitching their fearmongering to a gullible majority. Government is never a path to peace and prosperity, because it always operates through violence and theft. Whatever the topic, this is always the core truth people overlook. It cannot be twisted to good purposes.
Of course, the increase of authoritarianism always steps too far, and then ratchets back to relieve the tension until the general populace becomes accustomed to the new status quo. then it clamps down again. This is the perverse inverse of the technological advances we have seen. We went in very short order from small black-and-white CRT TVs to small color CRT TVs to large color CRT TVs to the current explosion of flat screen HDTVs. What was once top-of-the-line is now obsolete thanks to progress. See also the advancements in computers and mobile phones for parallel rapid improvements. Good change is disruptive, but people are willing to finance these changes voluntarily. In contrast, government tells people they can gain more control by delegating authority they don't have in the first place to bureaucrats who promise to punish OTHER people more and more over time. And these liars and thieves promise that their victims are net beneficiaries somehow.
On the left, gun owners, entrepreneurs, and the religious are threats to be quashed.
On the right, immigrants, the poor, and those who choose any non-traditional lifestyles are threats to be quashed.
In their tug-of-war, we are the rope, and we are getting stretched thin indeed. Liberty has no place with such control freak busybodies.