Tactical v Security in the Abramsverse

[Amanda Rose]

I have had some questions regarding the tactical and the security positions:

This is the canon from Memory Alpha:

The tactical station is one of the primary stations found on the bridge of a starship. This station allows the tactical officer to control the ship's phasers, torpedoes, and shields. 24th century Starfleet tactical stations also often access/control communications functions as well as the ship's long range sensors. The tactical station may also be known as the "weapons station." (Star Trek II: The Wrath of Khan)

Some Galaxy-class starships secure phasers at the tactical station for security personnel use. (TNG: "Ship in a Bottle")

Starfleet Security was a branch of Starfleet responsible for safeguarding the Federation from outside threats, and for conducting criminal investigations.

One of Hikaru Sulu's assignments aboard the USS Enterprise from 2265 through 2270 was that of Security officer.
In the mirror universe, Hikaru Sulu was Chief of Security aboard the ISS Enterprise.
Pavel Chekov was in charge of security on the USS Enterprise-A in 2293.

The security chief (or chief of security) is the officer in charge of the security division of a starship or starbase.

In the Earth Starfleet, the armory officer was in charge of a ship's security department.

In the mid-23rd century Federation Starfleet a security chief, like Lieutenant Commander Giotto of the USS Enterprise, was not necessarily a bridge officer. (TOS: "The Devil in the Dark")

In the 2270s, the role of security chief was combined with that of the chief tactical officer. The chief tactical officer could be a separate position or be combined with that of helmsman or navigator. (Star Trek: The Motion Picture; Star Trek V: The Final Frontier; Star Trek VI: The Undiscovered Country)

Therefore, my conclusion to all of this is that Tactical is a subset of the Security Department and thus would have the same Chief.