"Dear Iggy1337 I realise you work in the community job center for the mentally handicapped and none of what you write can be considered professional legal advise and any way shape or form, but what are my options if I decide to visit the Netherlands?" So the question seems simple but there is no definitive answer in Dutch law or jurisprudence, I will try and explain it as follows:
Most importantly as an American tourist you are of no interest to the police and are far more potential trouble than any officer needs. While you as an American are best avoided this however changes if you act like a retard, pick fights, are publicly intoxicated, dodge public transport fares ect. Also offending/swearing at an on duty officers is a crime as is the usual resisting arrest BUT read the
Gypsy Fellow EU Citizens part at the bottom as you wil be very likely visit Amsterdam
First off:1) Any object (knives, spoons, bananas, headphones ect.) can be illegal if to carry it with the intent of using it as a weapon in self defence. Thus any object can be deemed a weapon and carrying (in a way ready to use) can be considered carrying weapon (and illegal) but this is not the full story.
2) Some objects are pre-defined as weapons like guns, daggers, swords ect. so they are essentially always out, and require a license that is in effect not issued because you can never prove you are in actual imminent danger.
3) For other objects that could be used as a potential weapon you will need some sort of plausible explanation for carrying it.
Very important here is to never ever acknowledge that the item had ANY self defence or weapon function -> "Why I never even considered such a thing could be used as a weapon officer", any subsequent hypothetical questions ("But you could use it to...") should just be ignored or just say the question is leading and you wont comment on hypothetical leading questions. Be prepared just to give up or put away any item in the unlikely event you encounter a officer that stops you. Household knives are quite tricky in the sense that you will need a good story, other items are easier such mulittools, screwdrivers or like mrs Iggy1337 needle pointed medical scissors that you could use like a push dagger ect.
As to self defence:Dutch weapons law is completely separate from a 'self defence' defence. Use can use any available item including an illegal hand grenade (yes legit jurisprudence) in a self defence situation. Be careful however to when there is a legitimate self defence situation as you will have a duty to retreat if possible
but you also can defend others from imminent bodily harm. You also have to be relatively proportional and not have sought the confrontation. Also we have a bit of a weird one in the sense that if you use exessive (keeping on punching some dude when he's no longer a threat) force beyond the self defence situation it would need to be justified by your temporary emotional state at being attacked.
This is all a highly complicated field of law and the above in no way does it justice but the general gist of it is covered. Combined this all means you might go free on the 'self defence' defence but get convicted of some (minor) weapons law charge. Also be sure to call 112 asap after any altercation to get the first police contact in, but if at all possible just avoid it all.
Other things:Watch out for mainly
Gypsy Fellow EU citizens pickpockets in Amsterdam. THERE IS NO REASON TO INTRUDE IN TO YOUR PERSONAL SPACE, any attempt is very likely a scam (including asking directions, asking to take a pic, and don't carry anything important in a backpack ).
Breda: Zakkenrollers slaan toe met ‘voetbaltruc’
Also do not hand over wallets ect to
Gypsy Fellow EU citizens claiming to be an under cover officer, just call 112 and ask for a marked unit/further instuctions (but always remember the police have no interest in you so this is highly unlikely)
Nep agenten op heterdaad aangehouden in Amsterdam. (4 jaar cel !)
For the rest it's of course enjoyable and there is quite a bit to see if you were so inclined just you keep your wits about you.
@Dc204