This is complicated, but let's say that the EU's arguments are all basically arguments for empires and they are happy to say so. Look at the recent speech by Verhofstadt where he praised empires and said Europe must become one. But that's nonsense. Literally all the bloodshed and horrors Europe went through in the 20th century were caused by attempts to unite it into a single empire. The bizarre lesson some people see in this is to keep trying.

Also, don't for one second think the EU is against nationalism or patriotism. They desperately chase both. Why do you think the EU has a national anthem? Why do it's supporters say things like, "we Europeans". The entire EU project is a project to craft a new form of loyalty to the state and a self-sense of tribal belonging. Those who don't think this new nation, with its so called "European values", is better than their current nations ... well, they're treated with contempt.

Finally, there are no problems to which the solution is empires. The world has more countries than ever, yet is also richer and healthier than ever. This correlation and trend can easily continue for long time.

You say:

> Literally all the bloodshed and horrors Europe went through in the 20th century were caused by attempts to unite it into a single empire. The bizarre lesson some people see in this is to keep trying

Here is a response to this from [0]:

> Within the zone of integration, there has been no conflict since 1945, making it the longest period of peace on the western European mainland since Pax Romana

So from this there are two possible conclusions:

1) Either empires are good for peace

Or

2) EU is not an empire and it is not trying to be

Regarding:

> Finally, there are no problems to which the solution is empires

First: there are problems which cannot be solved by each state. See global warming for example

Second: The collaboration between countries is not mandatory to be an empire as form.

[0] https://en.wikipedia.org/wiki/Pax_Europaea

Edit: formatting and adding quote author

I understand this argument but find it brittle.

Firstly, yes, empires can be good for peace in some ways. The Roman Empire had Pax Romana. But the Soviet Union was also internally fairly peaceful, at least as much if not much more than the Roman Empire. Oddly enough, lots of people didn't want to be a part of either empire. There are downsides to empires that outweigh enforced "peace".

Secondly:

EU is not an empire and it is not trying to be

I think you missed a possibility: the EU is not an empire yet but is trying to be, and this is already causing various kinds of conflict. The fact that it's not creating World War 3 is no excuse: the Soviets didn't cause World War 3 either but not many people think the USSR was a good thing.

For an empire to dominate people it must have at least two things. One, a large number of people physically within that population who are loyal to the regime. Two, military strength to swiftly put down any rebellions and ensure the loyalists remain in power.

The EU has the first in abundance, as the horrible situation in the UK is showing. People were given a vote. The British establishment are refusing to implement it, as they're more loyal to the EU than to their own voters. This is no surprise because the same pattern is observed throughout Europe, where the EU creates a constant series of constitutional crises. Democracy is being crushed throughout the continent without a shot being fired due to the massive weight of regime loyalists already in positions of power.

The EU doesn't yet have the second. But it wants it very, very badly and has identified an EU army which reports directly to the Commission as its new top priority. Why does the EU need an army when NATO exists and works? Nobody can quite explain that. But let's face it: people keep voting in anti-EU politicians throughout Europe and if current trends continue, eventually one of these power struggles will be lost by the loyalists. The only way the EU could then keep control is by suppressing anti-EU citizens through force. If the local police won't do it, an EU army will be ready to step in and enforce Commission policy. It's hardly going to be useful for major conflict anytime soon given its size and newness, but as a form of ultra-loyal police it won't be half bad.

I'm personally planning based on the belief that the EU will be a new USSR-style empire before I reach retirement, complete with ability to put down insurrections, a large propaganda apparatus and ideological loyalty of at least 100 million people. I expect to die of old age with it firmly in control of most of Europe.

Finally:

Second: The collaboration between countries is not mandatory to be an empire as form.

I completely agree, so why are we building one? The useful work the EU does could be better done by a constellation of standards bodies and independent political alliances. The politics of unity and Europeanism that comes with it is unnecessary and dangerous.