As it turns out... not so much. Credit Suisse? Leveraged 40 times. UBS? 64 times. And their balance sheets? Perhaps ten times Switzerland's GDP. Iceland's bank liabilities were only 8.5 times GDP when they collapsed and essentially took down Iceland's economy along with. And like Iceland, Switzerland is not in the EU or the eurozone, and has no access to their larger protections.
One of the things you learn if you actually read Capital is that Marx was in fact a keen analyst; watching him pick apart the structure of nascent industrial capitalism is a great pleasure. And one of his conclusions was that capitalism will invariably destroy itself. His predictions on what would come next, maybe not so much, but on this at least Marx was right.