Government as a Threat
To this point, I've discussed the need for government and some derivative issues concerning how these needs are satisfied by a government. But anyone with a slight familiarity with the history of liberty will recognize that government itself is usually the biggest threat to individual rights. To get a better understanding of the structure and theories of government, this is a major fact that cannot be ignored.
The problem is obvious. If there's an organization responsible for deciding what is or isn't a proper use of force, they can and often do decide that their own uses, no matter how morally illegitimate by objective standards, are just fine. This is compounded by the fact that governments usually have a strong Executive branch capable of forcing people to accept its decisions, no matter how wrong they are.
I think the reasons and methods by which a government abuses its position are well-known, so let's just move on to what needs to be done about it. There are countless methods for minimizing the possible corruption of a government, so this will be a short survey, in no particular order.
The first method has already been discussed in a different context. The three functions of government—Judicial, Legislative, and Executive—can be separated into different branches. By splitting the powers, any single branch can prevent the others from carrying out an injustice. A use of government power requires all three branches of the government to cooperate.
Checks and balances is a system that pits the three branches against each other. Each branch is given power to interfere with the other two branches. This comes in many forms. Some branches are able to impeach members of the other branches. In the US, the President has a partial veto over legislation. The Supreme Court can declare a law unconstitutional. The legislature pays the salaries of the other branches, etc.
The government can be constrained by a constitution, which specifies the fundamental limits of the government, and the limited powers it has. A Bill of Rights can further limit the scope of government.
Democracy, or the ability to periodically vote for members of the government, allows the voters to occasionally change the participants in the government. They may also have the ability to change the structure of the government itself, or directly undo bad laws.
Federalism is a system of smaller government under a unifying larger government. The larger government's scope is reduced and the responsibilities are then given to the smaller governments, such as state or local governments. By removing the responsibilities of the higher-level federal government, it reduces it's range of legitimate action. The smaller governments may be more easily controlled by their constituents, reducing the chances of governmental abuse.
The law itself limits the government by having an objective standard to repair to. The law limits the government by defining exactly where it has authority, and consequently where it is overstepping it's bounds.
As I said, this is just a survey, but you can already see the implications. The very structure of government is often defined based on the needs to protect individual rights from the government itself. The means there are two basic issues related to the structure of government. The government needs to be able to protect our rights without becoming a threat itself.
I have written an article on how principles can be used to stand up to government tyranny.