This court decision is troubling on other levels too.
1. The states have always handled marriage and family law. Now there is a strong federal component with the Supreme Court having imposed their view of what marriage should be.
2. The Supreme Court, and other courts before this time, took it upon themselves to change the definition of a legal term, as well as the dictionary definition of a word. In order to achieve their goal, they had to change the definition of marriage.
3. The fact that citizens of 32 states, separately from each other, decided to go through the process to amend their constitutions to define marriage meant nothing to the five liberals on the Court.
4. The fact that a handful of states had changed the definition of marriage through the political legislative process was noted by the court, but the fact that most states had reached the opposite conclusion of how marriage should be defined was meaningless to the liberals on the court.
5. Only two years ago, the Supreme Court ruled that since some states allowed homosexual marriage, the federal government must likewise do so. Under principles of federalism, the court decided that the states were the ultimate arbiters of how marriage should be defined. But with this ruling, they completely reversed their own reasoning and did not care how states defined marriage. Instead deciding to impose their own definition of marriage.
Your points are right on. In essence what this ruling by this court did was to place possibly the final nail in the coffin of federalism of the central government and replace it with a unitarian central government. State boundaries are now just lines on a map.