The title is slightly confusing. According to AP,[0] current participants are 48 States, Washington DC, and Puerto Rico. California and Alabama are not involved.
oh but title said territories plural, red alert
The original title seems like the best option. Also, D.C. is a territory in a loose sense (part of the U.S. but not a state), just not the same formal category of territory as Puerto Rico. It's an immaterial distinction in a headline such as this.