[graemep]

There seems to be no reason given for why this would be good, nor does it address the reasons why enlargement has not happened.

Would people in the EU be generally keen on the largest EU country being a not quite white enough Muslim majority country? Would they like EU borders with Iran, Iraq and Syria?

He implies its the threat posed by Russia. The EU is not a military alliance. There is a reasonable argument that Europe needs a military alliance that is not dependent on the US, but the EU is not it.

In many ways enlargement weakens the EU, as does "ever closer union". Both create more internal division. The UK would not have left if the EEC if it had remained the same organisation it was in the 80s.