Is this enough to go to war over? Maybe, maybe not. Clancy will probably not want her standing trial in any kind of public forum due to the knowledge that the Tal Shiar was able to penetrate Security at all, much less to that level would seriously erode the public's trust in Starfleet.
Per se, Oh's infiltration of Starfleet Security is probably not actually enough to go to war over if we look at real-world history.
The most obvious comparison would be to
Kim Philby, a Soviet mole who infiltrated and achieved high rank within MI-6 before being exposed and fleeing to the Soviet Union in 1961; the United Kingdom did not declare war upon the Soviet Union, even though Philby had cost several lives and done terrible damage to their intelligence operations.
But I think an even better comparison would be to
Robert Hanssen. Hanssen was an FBI agent who spied on the United States government for both the Soviet Union and for the post-Soviet Russian Federation, from 1979 to 2001.
I think Hanssen is a really good comparison because the political situations are fairly well analogous. In real life, the Soviet Union collapsed in December 1991, and several different states emerged that had previously been part of the USSR, including the Russian Federation and Ukraine. We know from PIC that the Romulan Star Empire either collapsed or splintered some time after the 2387 supernova, and that the Romulan Free State is either a successor state or a "spin-off" state that has achieved diplomatic recognition from the Federation. Though the following details are not at this point canonical, showrunner Michael Chabon's Instagram posts have indicated that the writers' intention was that the Star Empire had collapsed, and the Free State is the most powerful of several successor states that have emerged due to the backing of the organization that either is still or was once known as the Tal Shiar.
The canon seems to imply, but does not explicitly state, that the Romulan Free State is less hostile towards the Federation than the Star Empire had been. We know that the Neutral Zone had been finally abolished after standing between the UFP and RSE for over two hundred years, for instance. I think the biggest implication that the Romulan Free State is less hostile towards the Federation than the RSE had been, is the Borg Artifact. If the Free State had uniformly hostile intentions, it seems improbable that it would have invited the Federation to send its scientists to help study the cube or to help revive and rehabilitate ex-Borg drones. Under the old regime, the Romulan Imperial Fleet would have secured the cube, and the Star Empire's officers would have likely killed or imprisoned the inactive former drones and have tried to reverse-engineer Borg technology for their own exclusive military usage. Yet we know that the Free State actively signed a treaty with the Federation over the cube's fate and was allowing Federation scientists to study its technology along with them.
But, we
also know that the Tal Shiar remains a significant power within the Free State, and seems as hostile and authoritarian as ever. But the Tal Shiar also appears to be under a certain amount of hindrance from the Free State's government. Indeed, Narissa seemed to be implying that she had needed a legal basis for seizing control of the Artifact and executing Hugh under Free State law -- rather than just having carte blanche to seize control and do whatever she wants, which the Tal Shiar used to be able to do on Romulan Imperial Fleet ships per TNG's "Face of the Enemy." And of course, the Tal Shiar fleet backed down from attacking Corpelius after Captain Riker invoked the Free State's treaty obligations towards the Federation -- implying that the Tal Shiar did not have the authority to commit the Free State to a major war and would find itself in conflict with its own government if it tried to carry out its anti-Synth mission.
Now, the situations don't line up exactly perfectly. We know that in real life, Robert Hanssen was a United States citizen who turned traitor after joining the FBI. PIC is unclear whether Nedar was originally from the Romulan Star Empire and infiltrated Starfleet under a false identity, or if she was raised in the Federation to be secretly loyal to the Zhat Vash and Tal Shiar.
But the broad parallels do line up. The Soviet Union collapses; the Russian Federation emerges as the most powerful post-Soviet state; Russia maintains the support of the KGB (now known as the
FSB, but really it's the same organization with a different name) while also trying to go for friendlier relations with the United States and a more open society. The Romulan Star Empire collapses; the Romulan Free State emerges as the most powerful post-RSE state; the RFS maintains the support of the Tal Shiar while also trying to go for friendlier relations with the United Federation of Planets and a more open society.
Robert Hanssen was exposed in 2001 after spying for the Russian Federation for ten years and for the Soviet Union for a previous 12 years. We know that Nedar started infiltrating Starfleet under the name "Oh" some time after Data was discovered, presumably as part of a long-term project of seeking out and destroying Data and other Soong-type androids. We know the Romulans were in self-imposed isolation until the early Borg incursions forced them out of seclusion in 2364, when the Imperial Fleet made contact with the
Enterprise-D. I would hypothesize that Nedar began her infiltration circa 2365 as a direct result of Data's presence being observed on the
Enterprise bridge -- meaning that she had been spying on the Federation for the Tal Shiar for around 34 years as of "Et in Arcadia Ego, Part II; compare that to Hanssen spying on the U.S. for 22 years when he was exposed.
So, in both instances, you get these long-term moles who've done tremendous damage to domestic security operations, on the behalf of a hostile foreign regime that collapses and then on behalf of a friendlier successor regime that still wants to be able to spy on the other side even if they're not looking to be actively enemies.
Now, on that basis alone, I think the Hanssen situation is illustrative. In 2001, the United States uncovered Hanssen and arrested him; they didn't send him to Russia or do any sort of prisoner exchange with him, but they also didn't go to war with Russia, or even really fundamentally change U.S./Russian relations. The U.S. and Russia were still trying to be buddy-buddy, especially after 9/11. Relations only stated to get worse in 2008, when Russia invaded Georgia, and only definitively got worse in 2014, when it invaded Ukraine.
So, Nedar's infiltration of the Federation likely won't mean going to war with the Romulan Free State. Especially since the Free State can just counter that a Federation citizen, Hugh, tried to size control of the Artifact and use it against the RFS, claiming that he was trying to seize Borg military tech secrets for the Federation. So it's tit-for-tat there.
But! This next part does raise major questions about how the Federation should respond:
At the same time, the knowledge that Romulans were directly responsible for what happened on Mars is going to come out eventually,
The news that the Romulans were behind the Mars attack is going to come out now, no? The Federation rehabilitated the synths. It will need to explain why.
Nedar is directly responsible for the deaths of over 92,000 Federates, the destruction of the Martian surface, and the destruction of numerous Federation starships and the Utopia Planitia Shipyards. This would normally constitute a clear act of war.
But. It is not clear on whose behalf the attack occurred, from a political sense. Yes, the Zhat Vash -- but are the Zhat Vash an agency of the Romulan state? The attack occurred in 2385, when the Romulan Star Empire still stood. The Star Empire is gone; the Free State doesn't seem to want to be at war with the Federation or to have any knowledge of the attack themselves. Should the Federation sunder the progress in relations between the RFS and UFP, or should it treat the Zhat Vash as a rogue conspiracy within Romulan society?
I expect the Federation may well demand the Free State hand over Nedar; if they refuse, I expect that might lead to a major freeze in Federation/Free State relations. We might see the re-establishment of the Neutral Zone, especially after Federation citizens hijacked the Artifact.
But, I don't think we'll see either side going to war. The Federation probably understands that it's not clear if the Free State has control over the Zhat Vash, and the Free State seems to have a major interest in trying to build a better relationship with the UFP. It's not like they have other allies to turn to as far as we know.
and the Federation would have a perfectly legitimate excuse for the use of force against them.
Who's "them?" The Star Empire? It's already collapsed. The Free State? No evidence they knew about the attack or have any control over it. Hell, the Tal Shiar/Zhat Vash appear to have conflicting goals with the Free State government in "Nepenthe."
Also, the Federation isn't in the business of looking for "excuses" to go to war.
She could also develop into a recurring adversary for Picard's new crew. Any usefulness she had to the Tal Shiar is now over. Granted she probably made further inroads than any asset save Nanclus from TUC
Nanclus was the Ambassador of the Romulan Star Empire to the United Federation of Planets. Foreign ambassadors are not exactly the same thing as moles.
but any intel service worth its salt burns assets once they have been exposed, and no matter how high she got, she cant go back to her cover. In the eyes of the Tal Shiar, she's also probably damaged goods as well since they probably don't look too well on failure, and may offer her up as a sacrificial lamb to the Federation in the hopes of sweeping this under the rug. (I dont see the Romulans as the type of culture who would quietly reassign someone to a strategically unimporant posting as a consequence of their failures.)
I could plausibly see the Free State offering Nedar up to the Federation, particularly if the Free State government genuinely wasn't party to the Tal Shiar's/Zhat Vash's plans and wants better relations. But I could also see this leading to the Zhat Vash members within the Tal Shiar to make the decision to have the Tal Shiar withdraw its support from the Free State, and either defect to one of the other Romulan states, or even establish themselves on their own.
The Zhat Vash are secret police within secret police.
I think the Zhat Vash are less a secret police than something akin to a secret religious order. Their goal isn't to maintain the power of the state; their goal is to enforce their ban of synthetic life in Romulan society. They look less like a part of the Romulan governments to me than like a conspiracy within those governments.
Oh is Keyser Soze... she and her entire fleet will just disappear to parts unknown until needed. She reports to no one, apparently, unless they decide to introduce a superior.
Yeah, the whole thing where she's been a mole within Starfleet for decades while
also being a general within the Tal Shiar seems... improbable. Poetic license, I suppose.
I'm sure Section 31 will be happy to keep an eye on things.
I seriously hope that by 2399, Section 31 has been exposed, its agents brought to justice, and its infrastructure dismantled.
Where were s31? Some serious questions to be asked by themselves as why they let Oh continue in role.
Seems pretty obvious to me: they were fooled just like Starfleet Intelligence, Starfleet Security, and Federation Security. Remember, Nedar had probably been infiltrating Starfleet since the 2360s.
Sure they wanted the supernova. Maybe even the synth attack,
I can see Section 31 wanting the supernova, but I have trouble imagining them considering the destruction of the Utopia Planitia Shipyards to be an acceptable loss in service of any objective. They would never want to weaken the Federation.
Not surprising. Unlike ambassador T'Pel, who we never saw again, a return engagement of Oh should be a lot of fun. She can be the new Tomalak, only less camp.
I wouldn't be surprised to see Narissa again too. She transported out of a jam with the xB's and never left the cube.
I would love to see Nedar return along with Jamie and Cersei*. They'd made for great recurring villains now that they have this history with Our Heroes.
*
(My affectionate nicknames for Narissa and Narek.)