I glimpsed an article but can't find it now to give the exact reference saying that
pickpocketing has reached huge dimensions in European cities like Barcelona, Rome and Naples.
The Louvre in Paris has had actual gangs roaming around snatching purses or maybe even bolder aggression.
I knew of the former information generally ; when I was a student, Naples was considered VERY DANGEROUS.
But I had no problem and enjoyed my travels there and to Capri by hydrofoil.
Barcelona I purposedly skipped, never having any interest in that Gaudi "cathedral", nor anything else supposedly famous there.
Madrid was considered risky but again I had a great time there whenever I visited.
However I do remember now that my sister got pickpocketed immediately on the Paris Metro.
In retrospect, I am sure it was easy as pie to see that she was not French due to the way she behaved.
She was standing right next to me and never even noticed it til time to produce money much later...
So remember == and this goes ESPECIALLY for American travelers to Russia -- the locals can see you a kilometer
away as being a foreigner, thus a possible target.
Don't speak in English in public or act strange or draw attention to yourself ; blend in.
Observe how LOCALS dress and look and act and imitate it to the extent possible.
It is no time to flounce around and assume that Americans are king. They aren't anymore. If they ever were !
Rather than expecting foreign nationals to speak English, as many naive Americans going abroad do,
pay attention to learn basics of language and if visiting Russia or Ukraine, learn the Cyrillic alphabet right away.
Not when you get to the first Moscow Metro station....
Above all, guard your bags carefully and do not flaunt those phones which are so much in demand internationally.
Don't leave a phone or some electronic thing lying out in view the way people often do to look important [my observation !]
Assume you are being watched by a potential pickpocketer and behave discreetly.
Finally, if something does happen, run right after the person ! A friend of that same sister who had lived in Italy several years
had her purse grabbed in the Rome train station. She took off after the man, and managed to get a hold of her purse as he ran.
She didn't know what to do as they both gripped the purse, so she hit him over the head with her bag !
It created enough of a public scene to make the assailant, after a long tug-of-war, let go of her bag and run away abashed.