This has to be satire.... so much bad information...
No, it was just their first attempt. Be more tolerant.
How are 'wojna' and 'walka' supposed to be different?
Similar terms but still different. Like war and fighting. So, you can have a war and it usually involves fighting, but there might also be fighting without war. Simple.
And how many orthodox Jews would marry (presumably non-orthodox Polish women?)
Yes.
This excerpt is really dumb and I feel sorry for any kid who's misled by it...
Oh, come on, give them some time. Other countries have been developing such books for centuries, while Poland has just started.