And these securities are by no means straight public debt (the central bank is not using them to finance itself). They reflect postponed liquidity (they will be monetized when circumstances require so as it happened in the second half of 2007).
4 For example: Gregg P. and E. Tominey (2005) show that an early period of unemployment can lower wages by  up to 20% at the age of 42; See Gregg P. and E. Tominey (2005), “The wage scar from male youth unemployment”. Labour Economics 12 (4): 487–509.