the EU is currently struggling with a refugee crisis (mostly due to the civil war in Syria, or proxy cold war between the US/Saudis and Russia/Iran, as it has become much more than a civil war...) but that is not the EU's fault, the countries of the EU, members states, remain sovereign, and they can't agree how to best deal with immigration.
As for the economy. How can it be 'lagging behind'? we are already the largest block in the world by total GDP. 1% growth for a big number is more than 10% growth of a small number.
The fact is small poorer nations have a lot of low hanging fruit to grab. Easy options to expand their economies, while developed nations have already done these things. The have only more difficult options for growth. And the % will be smaller because they are already fairly large.
India and China may be growing faster, and will eclipse the EU in a few years, but they have over a billion people each living in various stages of poverty. When they drag themselves out of poverty, their total GDP will be large than the ~510 million EU citizens. Though China and India are far from being double the EU GDP rate... so in terms of absolute wealth, we are still doing very well.
Only the US can be fairly compared to the EU, and the US is in a huge amount of debt, fighting multiple wars, failing to provide basic necessities like health care, socialising the debts of massive banks (who privatised their gains). The US is not a model i would care to follow - especially not given their role in the refugee crisis, and the military actions against Syrians.