Does national debt matter?

If you want a quick lesson on how the fiscal policies of Democrats and RINOs are leading to disaster, here's a Wiki article (yes, I know) on federal debt. Scroll down to "Risks associated with debt," and watch as the authors casually note that

Debt held by the public as a percentage of GDP rose from 34.7% in 2000 to 40.3% in 2008 and 70.0% in 2012.

Most people look at that and think "Cool--the public was so flush with cash that it was able to invest a *whole* lot more in government debt."  But you need to know that by "the public," the authors mean U.S. borrowing from any entity other than another federal agency.  So rather than write "we owe China a shitpotload of money" they write "debt held by the public."  Much more soothing.

They then quickly spin a couple of "no-problem" scenarios based on totally ludicrous assumptions--like assuming that deficit reductions specified in the Budget Control Act of 2011 will occur as specified by that law.  But of course congress essentially erased those spending reductions three weeks ago--as everyone knew they would.

The positions and spin suggest that the authors are Democrats trying to reassure everyone that fast-climbing debt is no problem.  In fact they actually write

Economists debate the level of debt relative to GDP that signals a "red line" or dangerous level, or if any such level exists.

Didja see how neatly they did that, citizen?  They don't want to flatly claim that it doesn't matter if a nation has a debt two or three times larger than its GDP, because even the dim-witted would sense something was wrong there.  But by couching it as "Economists debate the level that signals danger..." and adding "...or if any such level exists," they've planted an idea.  According to these folks, debts don't matter.

But isn't it interesting how the media screamed that rising deficits (the things that cause debt to rise) were a ghastly, scary, life-threatening problem when G.W. Bush's administration had deficits a third as large as Obama's?

Gee, what in the world could account for the reversal of their position?