From George Magnus in the FT:
Markets may derive some comfort from this initiative in the short-term as default risks are reduced, but like all financing measures, it only buys time in which economic depression will undermine it. And by effectively binding banks and sovereigns even more closely together, it is a roundabout route to nationalisation of sovereign finance, which ironically, makes fragmentation of the euro more likely.
And here is John Cochrane, in what is generally a provocative essay:
Indebted governments have been pressuring banks to buy more debt, not less. As banks have been increasing capital, they have loaded up even more on “risk-free” sovereign debt, which they can use as collateral for ECB loans. The big ECB “liquidity operation” that took place yesterday will give banks hundreds of billions of euros to increase their sovereign bets. Bank depositors and creditors have figured this out, and are running for the exits.
By stuffing the banks with sovereign debt, European politicians and regulators are making the inevitable default much more financially dangerous. So much for the faith that regulation will keep banks safe.