When a libertarian in America criticizes the potential abuse of a government power, a common response is that it can't happen here.
Take the raging debate on gun control. Libertarians point out that the number one reason to fear more gun control is that the government would then have a legal monopoly on the ownership of guns. Libertarians will point out that governments killed well over 100 million of their own people in the 20th century alone. Libertarians will point out that gun control was used against the Jews in Nazi Germany before they were rounded up.
Of course, the common response is, "it can't happen here."
Here is a good dialogue between a libertarian and a gun control advocate:
Gun Control Advocate: Don't you think we need more gun control?
Libertarian: By whom?
Gun Control Advocate: By the government
Libertarian: No, I don't. But the good news is that Americans are already well-armed and are not likely to give up their guns.
Gun Control Advocate: But why shouldn't we try to disarm Americans.
Libertarian: Because then only the government will own guns and the government could become tyrannical and it would be more difficult for the people to resist.
Gun Control Advocate: But that can't happen here in America.
Libertarian: You are right, because we are well armed.
With Rand Paul's filibuster in the Senate, there is now a lot of talk about the use of drones, particularly in America. (For the record, I think it is just as wrong to use weaponized drones in foreign countries). Republican senators, such as John McCain and Lindsey Graham, both as pro-war as you can get, are criticizing Paul and others. They are essentially giving the line that it can't happen here in America.
Here is the whole ironic thing about it. If we had more people like John McCain and Lindsey Graham in this world, then it most certainly would happen here. They are both thugs and would not hesitate to use violent force against others. I don't think their character would change any if the target were an American with whom they disagreed.
Perhaps they are right saying that it can't happen here. Only time will tell. But if it doesn't happen here (although in some ways it already is, just not with deadly drones), it will be because of libertarians and others who are warning of the dangers. If we didn't have libertarians and others standing on principle, then we would most assuredly see even much greater abuses of power than we already see. We would probably see even more war and less in the way of protections of our liberties.
In conclusion, there are many who say that it can't happen here in America, in discussing the government killing its own people en masse. But if this is the case, it is only because of the people pointing out that it can happen here, that it won't happen here.