Princess Unicorn Bunny Kitten Angel

To put it bluntly it doesnt do shit.

Octavian is seemingly the only roman that cares about the Argos attack on New Rome, the gods are literally the same character with just their names swapped, and the greeks dont find out about the war happening until mid-late House of Hades.

Reyna watches her second home be attacked by a ship carrying the two people who she blamed for the destruction of her first home and then takes Annabeth at her word about the eidolons, Octavian is Bad Guy™️ so he can't be seen caring about anything other than himself, and the background characters are all tragic victims of Octavians manipulation and the reader must ignore that the romans were more than happy to attack the seven before Octavian even got off the Argo.

The gods are supposedly being torn between their greek and roman halves but they literally aren't.

Despite the Romans demanding revenge for the Argo attacking, Nemesis' roman counterpart Invidia is nowhere to be found. Baccus is just Dionysus with a different soda preference. There wasnt any different between Venus and Aphrodite. All Mars and Ares did was give Frank a headache. Hecate was all greek with no sign of Trivia and the opposite is true of Bellona and Enyo.

The only god that showed signs of being "torn" between greek and roman was Victoria/Nike. Even that didnt matter cause she was barely in the story.

The war also just freaking stalled once the Seven left Charleston.

It took about half of Mark of Athena for the seven and the roman legion to cross the entirety of America. It then takes the roman legion almost an entire book length to get from Charleston to New York City (mid MoA to early-mid HoH). Even then it takes until the almost the end of Blood of Olympus for Reyna and Nico to get to long island and deal with Octavian and his allies.

oops...