Is a systemic collapse starting to happen now?

I started this blog because I was worried about the national debt skyrocketing into hyperspace.  My current thought is that we have until about 2025 before that will happen.

What I am worried about now is independent of that, which is that the world economy, based on debt, is starting to collapse.  That we are entering a depression.  This started to happen in September 2008 with the collapse of Lehman Brothers. But the problems that led up to September 2008, namely too much debt, still exist.  The whole world is entering a liquidity/insolvency crisis and it will be cash & carry from here on out.

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Read this comment from http://www.zerohedge.com/news/cme-goes-margin-defcon-1-makes-maintenance-margin-equal-initial-everything:
"Every dollar owed relies on another borrower to borrow.  This is the problem in the face of aggregate contraction. The issue we face as plebes is that the BANKS are the sole conduit of money into the economy.  So, when the economy grew, the banks prospered.  As the Bernank prints, the banks prosper. This is the point of the deflationists, credit becomes artificially scarce not because of individual borrowers' inability to repay but the fact that there don't exist the MORE borrowers in the future who will have to borrow the interest owed.  It's a systemic problem.  It's that proverbial someone else, the lack of growth, that prevents the system from functioning.

So, everyone has to repay, everyone has to put everything up front, everything real and in existence now trades at a premium.  The system can't grow to pay today's interest, so nobody will lend even if the individual interest or venture lent to would be viable.  The system in a state of contraction makes the credit growth necessary for a compounding interest system untenable, therefore lending ceases.

Today's principal P becomes tomorrow's principal P + interest I.  The system necessarily requires someone to borrow (request the creation of money) more at every future point time T+1.  It always has to grow.  There always must be more credit created.  A loan today can't be created, exist, be viable, be repaid, without that."
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To paraphrase the anonymous commenter, our economic system requires continuous growth in order to pay the compounding interest. When this growth stops, lending stops, and the whole system locks up, like an engine without oil. 

The only way to temporarily stop this is another bailout of the banks and/or more quantitative easing.  The only permanent solution is to allow a depression and widespread repudiation and default.