Apologies for the length, but I had to correct some misinformation.
"In Western Europe, where anti-semitism among the conquered gentile population was less severe [...]"
"But when Poland regained its independence in 1919, thanks to the Versailles Treaty, the nation degenerated into a military dictatorship which encouraged anti-semitism."
These statements are either facile and come from a position of ignorance and show a lack of discernment. Consider that:
* After Poland regained its independence in 1918/19, it had been a democratic republic until the May coup d'etat of 1926 under Marshal Jozef Pilsudski, arguably the most important figure in the creation of the Second Polish Republic and the rebirth of the nation's independence. This de facto dictatorship lasted for less than 10 years. I know that we like to superficially assign without question an absolute superiority to democracy and view dictatorship as an absolute evil, but this depends on the particular characteristics of a given society, its situation, and its present needs as well as the kind of dictatorship we have in mind. Poland had been wiped off the map 123 years prior and divided into three parts by a joint conspiracy between Prussia, Russia, and Austria. It is strongly argued that without a dictatorship that would hold the nation together and guard it from foreign malice and its notoriously bad geopolitical predicament, Poland would have failed to survive as a state. There was a need for stabilization and coordination. Democracy presumes a certain status quo and does not bear chaos in such circumstances very well.
* Under Pilsudski's rule, the situation of ethnic minorities (1/3 of the citizenry) actually improved considerably, though some of these minorities later colluded with the Nazi and Soviet regimes in exterminations of the Polish population. Pilsudski preferred to emphasize loyalty to the state over ethnicity, which was the policy of the National Democrats under Roman Dmowski, Pilsudski's arch-rival (and who purportedly argued that ethnic minorities can add salt to the soup, though too much can ruin or destabilize a society, esp. when they fail to assimilate). In fact, Jews viewed him very favorably and their situation improved greatly especially under Pilsudski-appointed prime minister Kazimierz Bartel. Worth noting is that Pilsudski's own wife was Jewish. So I'm not sure how the author drew the link between dictatorship and anti-semitism. Maybe he was looking for a cheap trope to appeal to to sell his story.
* The Polish variety of anti-Jewish feeling during this period was not racial in character. The "Jewish Question" concerned the problem of who and what Jews were in relation to the Polish nation. To say that Jews were being kept back is not really accurate. The situation was far more complicated. Many Jews who did assimilate were quite successful. However, it is false to assume that all Jews wanted to assimilate in the first place and simply weren't welcome. Many had no such desire and purposefully maintained a separation from gentiles. Many were Zionists. Many had German loyalties. Some had Communist sympathies. During an era of nationalism where the state was rebuilding and trying to survive against the threat of Nazi German and Soviet Russian aggression, unknown or divided loyalties were threatening. Furthermore, much of the resentment towards Jews, where it did exist, was economic in nature. While the aristocracy and the peasantry were about 2/3 Polish, the same proportions did not hold among the burghers where Jews were overrepresented. In other words, Polish-Jewish relations are complicates and require particular care if they are to be understood, not boorish generalizations that you often hear from bigots and the ignorant, no doubt the same people who use phrases such as "Polish concentration camps".
* The greatest number of people honored at Yad Vashem are by far Poles. This is true despite that fact that only in Poland did Germany impose a death penalty that could be extended to the entire family for aiding and hiding Jews.
Other than that, I'm not sure how convincing the main argument seems to be. Gun control, like many polarizing topics, exists in an anti-rational domain that elevates a tool to some transcendental, fantastic order of Manichean symbols: you either have those who equate guns with freedom and those who equate it with evil incarnate. It is my opinion that whether gun training and ownership is not a matter of principle but a matter of contingent factors and pragmatism. For example, since we're on the topic, I believe countries in historically geopolitically risky situation like Poland could benefit from widespread training if not ownership. Switzerland is arguably geopolitically safer place, but it has a trained populace in possession of firearms. The US has a very curious history with fire arms that differs from that of France, which does not mean stricter regulation of the gun market cannot be put in place. However, while gun ownership has been increasing, violence has been decreasing, esp. violence involving guns. There is no single number that can characterize the facts on the ground, but what it goes to show is that much of the "public debate" is merely the projection of preconceived notions, ideology, and emotion. There is barely any reason in it, merely arrogant presumption that the issue is obvious.