Of the 10 mostly post-communist countries that joined the European Union exactly a decade ago today, none has benefited more from membership than Poland. First and foremost, there's the cash: the country received £56bn in development funds between 2007 and 2013, money that was used to build hundreds of kilometres of highways and express roads as well as youth sports facilities, modern sewerage systems, kindergartens and pre-schools.

Add to that the £60bn earmarked for Warsaw in the EU's 2014-20 budget and the country will have enjoyed a windfall equivalent to roughly double the value of the Marshall Plan, calculated in today's dollar figures. And that does not take into account the tens of billions of pounds that Polish farmers continue to receive in agricultural subsidies from Brussels. What we are witnessing is, without doubt, one of the largest wealth transfers between nations in modern history.

Then there is the boost the Polish economy has enjoyed thanks to its booming exports, which mostly head to other EU countries. A year before accession, Poland generated an annual GDP of £130bn; by 2013, that figure had grown to £305bn. Meanwhile, GDP per capita has risen from 44% of the EU average on accession to 67% today and is forecast to reach 74% by 2020. Small wonder then that some nine out of 10 Poles support their country's membership of the EU, according to a survey last month .

But it is not just Poland's economy that has changed; it's the country's citizens as well. Young Poles today travel and study all over Europe, taking part in exchange programmes or just simply packing up their bags and heading for the nearest airport. Many have now personally interacted with folk from different countries and races or know people from their families who have. This was not always the case.

When I first arrived in Warsaw as a student in 1995, most Poles had had little or no contact with the outside world. Communism had ended only a few years before. It was common for non-white foreigners to get called nasty names in public. The country was going through a painful economic transformation, times were tough and its frustrated citizens were often coarse and gruff in their behaviour.

But a decade in the EU and a decidedly more prosperous environment has helped to civilise Poles, much as prosperity tends to do everywhere. Nowadays, foreigners of all hues can walk the streets at night without fear of attack by skinheads, as was the case too often in the chaotic 1990s.

Poles have also grown more confident of themselves and their country. Many have stopped viewing their nation as the eternal victim. A collective inferiority complex, shaped historically by the loss of independence and foreign oppression, is slowly eroding, although it will still take some time to disappear altogether.

It would be silly to claim that Poland has become a land of milk and honey for all and sundry. If that were the case, 2 million Poles would not have emigrated, mostly to the UK, after accession.

Unemployment, at almost 14%, remains stubbornly high and would surely be higher if so many had not left. Poland exports its furniture, food, cosmetics and unemployment, so goes the joke in Warsaw. For those who do have a job, wages remain low compared to "old" Europe, one of the main reasons the country is a darling of western multinationals.

On the social front, there are grumbles from the more conservative members of the commentariat who say Polish traditions are being eroded by the influence of nihilistic western pop-culture. While these critics have no qualms taking EU cash, they are derisive of some of the public attitudes expected in a member state, things such as respect for LGBT-rights, gender equality (there is no such thing as discrimination against women in Poland, they say) and rightwingers' favourite bogeyman – political correctness.

Some yearn for the days when you could say "faggot", "nigger" or "kike" in public without anybody making an unnecessary fuss. Today, the persecuted wail, their "freedom of speech" is being stifled.

But this cultural backlash is to be expected in a country that is one of the most ethnically and culturally homogenous in the world, being 99.9% white and 95% Roman Catholic. What counts is that Polish mainstream society has adapted to western standards in public behaviour admirably quickly.

All in all, most Poles, conservative and progressive, would agree it would be difficult to point to a decade in Poland's troubled history that has been as benevolent for the country as the last one.