Some points to consider:

- The US presence (USS Mt. Whitney, USS McFaul, USCGC Dallas) seems to be at about the 30,000 aggregate tons foreign navies are permitted to put in the Black Sea under the Montreux Convention.

- The other warships that recently entered the Black Sea are Standing NATO Maritime Group One (SNMG-1). They are en route three weeks of routine visits to Romania and Bulgaria scheduled last year. These include:

Spanish F-100 FFG Almirante Juan de Borbón (F-102)
German Bremen FFG Lübeck (F214)
Polish Pulaski FFG General Kazimierz Pulaski (F272)
American Oliver Hazard Perry FFG Taylor (FFG-50). She is scheduled to join the NATO group later; perhaps Taylor cannot enter the Black Sea at this time without violating the Montreux tonnage limits.

- Foreign warships are only permitted to stay in the Black Sea for 21 days.

- The Los Angeles SSN Dallas (SSN-700) is not in the Black Sea. Submarines from non-Black Sea states are prohibited in accordance with the Montreux Convention. A closer reading of the Wired.com article will show that it only states that Dallas was “in the area”.