Roughly speaking, both US and Eurozone have been caught in the same structural negative feedback loop. However, EZ condition is much worse and complicated as there are green shoots in the US real economy, i.e. housing markets though sustainability is uncertain.

1. Vicious Cycle (US and Eurozone)
Both economies are still suffering from the Great Recession, but
US: Modest recovery driven by rebound in housing market
EZ: Double-dip recession (esp. peripheral states such as Spain, in which u_rate is 25%) Much Worse
d
Real Economy
shol e
Thre n U_rat
o Political deadlock
FRB
Helicopter Ben Loans decrease US: Fiscal cliff
Fiscal austerity
EZ: Brinkmanship
Q
E among members
(Germany vs South etc.)
Loans default Taxes decrease
Much complicated
Bailout costs
Government Fiscal
Financial Sectors
Condition
Losses on Gov Bonds
L
T
R Both US and EZ have suffered from sluggish recovery, fiscal
O
O
austerity and political deadlocks. And central banks have solely
M
T
ECB prevented economies from collapsing.
Super Mario However, the economic and political condition in EZ is much
worse than those in the US.