Efficiently create dummy

What's the neat way to create a dummy from a list?
The code below is not replicable, but hopefully self-explanatory...

d$treatment<-rep(1,length(d))

notreat<-c("AR", "DE", "MS", "NY", "TN", "AK", "LA", "MD",  "NC", "OK", "UT", "VA")

#i would really like this to work:
d$treatment[d$st==any(notreat)]<-0

#but instead i resort to this
for (i in 1:length(notreat)) {
temp.st <- notreat[i]
d$treatment[d$st==temp.st]<-0
i<-i+1 }

Thanks, list!