We do have our own Muslims assimilated centuries ago.
Oh please don't bring that argument. That was a special case with specific circumstances that are impossible to recreate nowadays. Besides they always have been a tiny fraction of the populace and today their number dwindled even more.
Deriving from ancient historical facts a far fetching notion that somehow magically it would work in the same way today is wrong on so many levels that I don't even know where to begin to explain to you in a way you would have understand.
Plenty of Muslims here, and the number is growing daily
You say it in a way suggesting that you think it is a good thing. Well, I wasn't expecting anything else from you so I only point out for the sake of an unsuspecting reader that you're deeply wrong.
Looking back to the OP original question I must say that it wasn't well thought over question. Muslims as such in the today world are not much of a bother for Poland.
An ongoing 'situation' in Europe with illegal immigrants cascading over borders into Europe. Mainly from the Muslim world (but not only) that they have became a problem.
I mean to say that they became a part of the problem. Ever bigger issue waiting to be solved are policies of so called European countries, Greece, Germany, Italy, France and other sycophants of the EU.
That by countries I mean elites and ruling class of those countries are more than obvious, at least it should be obvious, them and policies they pursue. Their responses to the crisis and their problem solving abilities are on the all time low. Unless... there is something going on behind the curtains that the general public is unaware of, that is beside general incompetence and vainglory of the political class.
No matter, an idea of bringing in a large number of some strange people into Poland was an unspeakable idiocy. That would inevitably spelled disaster for Poland on a large scale. Luckily people in Poland seen a writing on the wall and voted for such a government that wasn't so deeply depended on the German support (wasn't that deep up the Merkel's A...)narrowly escaping that fate.
As a general rule inviting onto your own territory a large number of people from foreign countries in a short space of time creates all sorts of problems for all the involved.
Muslim however seems to be ongoing problem that will be there for generations.
If the rich countries have nothing against in paying the price of their involvement on the world's stage, that is their choice.
Poland has nothing to gain by following their example. Trying to coerce Poland to do that is just wrong. All the people of foreign origin in Poland who advocated such a course of action at the time, aren't friends of Poland and Poles. Quite the opposite.
Why Muslim are a special case? Isn't that obvious? They arrive from a different civilization. A civilization that view others people and ways of live as inferior and encourages religious beliefs that extermination of the different religion is not only a good thing but is a sacred duty of the faithful. All that makes Islam rather incompatible with Christianity and with liberal democracy.
Those who don't see that clearly are not that bright. Alternatively they're fanatical ideologists that cannot/are unable to apply logic and reason to the case.
Surely individual Muslim immigrants to Poland (as long as they pass basic criterion) cannot to be avoided. Nevertheless they should be vented and watched closely by the authorizes. It would be wise to exclude all kind of wahhabies from the Polish citizenship.