Before 1976 all debt could be discharged when you were bankrupt. First non profit student loans were exempt from protection in 1976. Then in 1986 private student loans were exempt from bankruptcy.
Think about this for a little bit. If you are a student and take out a student loan, what assets do you have?....Generally you will have on assets other then your future earnings potential that results from your college degree. Any person acting rationally would declare bankruptcy as soon as they received their college degree if they took out student loans as the consequences of filing bankruptcy are much less then the benefits. This would result in lenders loosing all the money lent and students getting a free education.
In 2005 chapter 7 bankruptcy protection was denied for anyone earning over the median income in their state regardless of how much debt they were in.
This is not true. There are more strict requirements to filing bankruptcy as a result of the 2005 bankruptcy reform, but you can still file chapter 7 bankruptcy under certain circumstances. Your comment about 'regardless of how much debt someone is in' just shows how people abuse bankruptcy by taking on excess amounts of debt in order to only have it discharged later in time.
Now in 2014 case law is gradually being created allowing 25% automatic wage garnishments for all debts. The rules are being rewritten and the masses are gradually being led into slave pens built using money that was stolen from us all.
Also not true. Creditors have long been able to garnish a debtor's income in assets (usually to the tune of 25%) if they receive a judgment against them. This is what gives a borrower an incentive to pay, as if the creditor was not able to force repayment by a borrower then the borrower would have no reason to repay, other then the fact that they would have difficulty borrowing additional money in the future, which would not matter because they would have just received "free money"
You also need to remember that any time someone borrows money they must "promise to repay" the amount borrowed plus interest; the creditor relies on this promise when they give the loan. If someone were to borrow money with no intention of repaying (as evidenced by them not repaying) then they are committing fraud as they made a promise they did not wish to keep