Looks petroleum based the way it penetrated the concrete and the Memorial.
Vinegar would do this to marble.....
I’ll bet a little carbon tet would take it right off.
It works best of anything I have tried, and I have been examining rock samples from oil based drilling mud for well over 20 years.
As for the puke(s) who did this, I think this would be a fine time to bring back public flogging and the cat.
I found out about this on Saturday when I called my contact in Rolling Thunder to ask a question about a totally unrealated matter.
Smitty was PO'd to say the least.
I saw our friend HK later that night at his place (ya'll know who I'm referring to), and asked him about it.
While he downplayed the damage a little, I could tell he was pretty PO'd as well.
Regardless of the limited damage, it's still a desecration of a National Memorial, and a slap in the face of a lot of my very good friends.
Someone has just signed their warrant.
We will find out who did this, eventually, and they will pay.