Oh wow, Germany is that high?
Well, to answer your question, it's because we have guns. Plain and simple. Guns themselves don't kill people, people with GUNS kill people.
You can't make the music argument, because there are plenty of countries with rap and hard rock music (see the UK, Canada, Australia, and Germany). You can't blame video games either (see Japan).
We have a lot of deep-rooted anger and racism in this country. That would be enough to want to kill. Allow us to have assault weapons in our hands, and don't be surprised about our murder rates.
As an aside: All of the countries you mentioned have generally (with a few exceptions of influxes here and there) the SAME rates of burglary, theft, vandalism, etc. But their murder rates are much lower. It is extremely difficult to own guns in those countries, but very easy to do so here. Do you really need any more evidence that it is the guns that kill?
Edit: regardless of your personal politics, "Bowling for Columbine" is an excellent documentary to see. Yes, you may think of the documentarian as a wacko, (I, personally, don't even care for him myself) but he honestly gives really really great *undeniable* evidence to support his argument.