Quantitative Easing and ECB monetary policy -2nd part-

The pursuit of price stability, although considered important, isn't the only connection that moves the Bank of England monetary policy, and whatever you don't find the emphasis you can see in the rules of the ECB. While the European Central Bank states that "the primary objective of the Eurosystem is to maintain price stability ...... The Treaty establishes a clear hierarchy of objectives for the Eurosystem ..... ensuring price stability is the most important contribution that monetary policy can do to achieve favorable economic conditions and a high level of employment, "the BoE said that" One of the main purposes of the Bank of England is monetary stability, ie stable prices and confidence in the currency ..... . the low inflation is not an end in itself. It's still a major factor in helping to encourage long-term stability of the economy. Price stability is a precondition for achieving a wider goal of sustainable economic growth and employment ".
The target level of inflation is set by the British Government and the Central Bank seeks to satisfy it through its decisions. He is currently 2% according to CPI (for the difference between CPI and RPI, see my post "UK Inflation"). The Bank of England does not require this level is steady, and did not even want to (if this was the purpose would be frequent changes to interest rates which would cause uncertainty and volatility in the economy). Monetary policy must therefore required in order to return to the level of inflation near the target in the most reasonable time possible.
In January 2009 in the UK  was introduced the system of "quantitative easing" (QE), officially the "Asset Purchase Facility (APF)." Initially concerned the purchase of private and corporate bonds needed to stabilize the credit market and allow larger companies to have greater liquidity, adopting a new purchasing system in place of the issuance of Treasury bills.
In March 2009 the QE was extended to the purchase of government bonds (Gilts).
"Quantitative easing" means inject money (not printing but creating it electronically, moving the reserves of the Central Bank) directly into the economy through the purchase of government bonds and (to a smaller part) private in the secondary market. These purchases are made through outright transactions, if it is true that the Governor of the BoE hopes that in future, once out in the strategy of buying assets, he received a reduction of the securities held by PAF and that this happens not only as a result of normal maturities of the bonds but also through sales of the same.
Thus in England the instrument of monetary policy has shifted towards the quantity of money supplied to the system rather than on its price, the interest rate (the exact opposite of what the ECB does). The initial goal is always to keep inflation in check.
Certainly the practice was introduced when the economic situation of the United Kingdom was in recession (negative GDP) and inflation falling. Not having the ability to operate on the reference rate (previously 0.50%) to stimulate the economy and in order to revive consumption and investment was decided to adopt this system as part of monetary policy, with an enlargement of the monetary base, through the banking system, that would boost the money supply and credit, and increase liquidity in the private sector, providing impetus to inflation and economic recovery.
In March 2009 it was decided by 125 billion pounds of APF, then taken in August and November of that year to 200 billion. In October 2011, coinciding with the crisis in the eurozone (which hit the UK as a major exporter), the Government has authorized the BoE to an additional QE of 75 billion for purchases to be made over the next four months, on the assumption that inflation (5%) is expected in the next year to fall  below the target of 2% (again see the post "UK Inflation" for reasons of inflation so high and the expected decline ). Indeed, it must be said that for this reason, many economists expect further steps of QE, there are those who assume we can get to 400-500 billion pounds.
The operational difference between quantitative easing operations and open market purchases by the ECB is that, while the latter are improvised, the former are, as seen, specified in the amount and in the period of validity of the purchases. The QE is then a well-defined and quantified signal of monetary policy.

The system used by the Bank of England, as seen, can lead to increases in inflation (after he was born for this purpose), but still connected to the increase in spending capacity of the system. The ECB cannot do that and does not want to do. It was practically forced to buy  Irish, Italian and Spanish bonds, but the motivation was to support prices and reduce the effects of speculation. Sure it lacks a tool to grow the economy. And in a recession, which brings clear reductions in the price level, having a weapon more than the single maneuver on interest rates would not be bad. It would be an indirect way of stimulating the economy, although it is true that the motivation that led, in 2009, to the creation of the QE program was to maintain price stability to support the government process of economic growth and employment (being the exchange of letters between the Governor and the Chancellor of the Exchequer), in spite of the theory of neutrality of money in the long term (the one that says, in summary, that a change in the amount of money in the long term changes the general level of price but not affects permanently  the real variables, ie product and employment).