From an economic perspective the EU can be criticised for various reasons
Common Agricultural Policy CAP
The CAP was one of the most inefficient economic policies and waste of money. It subsidised farmers to produce goods that nobody wanted. The excess supply was often dumped on world markets creating falling prices and incomes for world farmers. After many years, the worst excesses of CAP have been reformed. But, it remains persistently difficult to end the culture of subsidising agriculture. The taxpayer pays the burden of higher prices and cost to EU.
Regulated Labour Markets
Unemployment in the European Union has been persistently high for the past two decades. This is especially a problem in countries like France and Spain. One reason is the highly regulated labour markets that the EU social charter encourages. The EU has failed to deal with regional unemployment.
Anti Inflation Bias
The ECB has inherited the German Bundesbank’s anti inflationary stance. However, they often overdo this leading to lower growth. This is especially a problem for countries in the EU, who may struggle with a common monetary policy and interest rate.
Euro has Created Lower Economic Growth.
The EU pushed the creation of the Euro. However, in practise, member countries have struggled to cope with the fixed exchange rate, and lack of independent monetary policy.
Countries in the Euro have been pushed into bond crisis because markets fear a lack of liquidity (ECB can’t act as lender of last resort and print money to buy bonds). This has seen higher bond yields on debt of Euro countries. As a result of bond crisis, governments have been pushed into spending cuts and budget austerity.
However, despite the fiscal austerity, there is no alternative for promoting economic recovery. Monetary policy is set by the ECB. As a consequence economic growth in the Eurozone has been disappointing.
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