Ok, this here is going in the wrong direction.
TS is American, the right to bear arms is universally recognized in all U.S. states and is a significant part of American identity. Please don't treat him like a koala bear on an eucalyptus-fuelled rampage, he's just being American.
1) You will not be able to carry Your U.S. firearm in Poland.
2) The chances of You legally obtaining a CCW for a firearm for self-defence purposes in Poland are 0%.
3) There is no such thing as a "gun at home" in Poland. Each and every gun requires a proper permit ( rifles, shotguns ) or a CCW ( pistols ), regardless of where You store it and where You take it.
4) People that I personally know in Poland who obtained CCW's and aren't "hunters" usually fit the same mold: former Polish police/military, formerly employed by one of the local 3 letter agencies or businessmen who happen to be extremely well connected locally. Oh, yes, and politicians.
You do the math.
5) Right of self-defence in Poland is extremely different from what You've got in U.S. and the "castle doctrine" doesn't exist. If a man attacks You and You shoot him dead You will be in trouble even if he had 5 inches and 150 pounds on You. Running for the embassy does seem Your best bid in such a case.
6) Having a "weapon" ( notice, I stopped using the term firearm, pistol, etc. ) in Poland without a proper permit is a criminal offence. Same applies to firearm ammunitions. Jail sentences are not unusual.
7) A "weapon" is ********** defined by appropriate Polish law. Not going to get into the details, but let's just say this:
A baseball bat is a weapon ( named as such in the appropriate legal act which I believe was quoted here ), requires a permit and You can go to jail for having one without it. Apparently it became some sort of a boogeyman in the 90's, hence this stupidity.
A knife is not considered a weapon for the purposes of needing a permit for it ( see appropriate legal act ). Neither is a machete. Or a sword, battleaxe, ranseur or bec de corbin. Why? They're not in the said legal act. You can carry them, even openly. But if You use them they'll be considered as weapons for the purposes of deciding what crime You actually committed.
Yeah, I know, welcome to Eastern Europe.