Federal spending info shows interest payments are main category growing recently, not defense nor healthcare

After a discussion with a co-worker on if defense or medicare grew more recently in U.S. federal spending, I did a bit of research.
It seems as a percentage, neither grew recently.  Or in-other-words, both grew equally outrageously.  This surprised me some.

Here is a link to a chart of relative federal spending categories since 1962.  It looks like the main category growing, as a percentage of total, is interest.  (And that is with the relatively low interest rates recently...)
http://www.heritage.org/research/reports/2010/06/~/media/Images/Reports/2010/sr0078/sr78_chart2a.ashx?w=600&h=1063&as=1

The chart is from a fairly long, detailed article that I only skimmed through from the Heritage Foundation: Federal Spending by the Numbers 2010

It looks like both defense and safety net (a.k.a. entitlement or income redistribution) are both growing about the same, very large, rates.
This page also states:
> These deficits would not only raise interest rates, they would also nearly quadruple the net interest costs of the national debt over the next decade.

The article also has a "Nowhere to Cut?" section including some items that should be easy for any politician to cut.

So default now on loans or default later or get spending under control by doing very difficult things.
My guess of the outcome, based on the self-control of our leaders and the majority of population that elect them, is default on the loans.
Hence my idea that it is better to get it over with quicker when the pain will be less.
If we could find a soft-landing method, I would be all for it.  But I doubt we as a nation have the self-control.  Recovering addicts seem to have more success with cold-turkey than gradual reduction, even though it appears very mean and unkind.

Later,
Howard