In my head canon I imagine time travel being a lot harder to successfully pull off than one might think being the reason for its absence as a weapon of war. But reading this thread got me to wondering if there are other reasons. We know there are laws regarding time travel, but I mean look at the laws regarding warfare today: they're only as effective as they are enforceable. And I wouldn't trust any single people with the power to wield or thwart its use.
I wonder if instead every major power that is capable of time travel, like a WMD, keeps it at bay, knowing that using it means having it used against you in Mutually Assured Destruction. If there aren't chroniton-protected fleets or bases or time travel devices that are immune to immediate changes in the timeline and from which counterattacks could be launched, in the present (using the fleets) or the past (using the devices).
So there is detente between enemies of comparable ability and perhaps interstellar treaty banning using time travel against less advanced aliens for various reasons. Might be interesting to see how those treaties are bent and broken and less absolute where they're harder to enforce.
In my head canon for the 26th century, the ban on Time Travel during the 32nd Century "Post Burn" was due to the PTB (Powers That Be) not being able to find a "Absolute Win" scenario. So everybody was forced to call a truce and just ban Time Travel so it doesn't make the Time-Lines worse for everybody.
The
Temporal Accords had "Regulated Time Travel" for Scientific Study Reasons, not Personal Gain reasons, for the UFP and all signees of the Treaty.
The UFP had Time Travel from the start of the 26th Century to the 30th Century.
For nearly 400 years, Regulated Time Travel wasn't an issue.
After a certain point in the 30th Century, there was the Temporal Wars started by new Temporal Powers who wanted to change time for "Personal Gain" reasons.
That's what sparked the war.
But what DISCO & the USS Discovery did was bring the ability to Spore Jump to the future. There were unintended consequences to do so that could affect the results of the "Temporal War".
But the more important part was the "Genetic Augmentation" necessary to become a "Biological Navigator" also allowed you to
partially exist outside the universe's normal flow of time.
This gives you a sort of "Natural Defense" against Temporal Weapons & Effects.
Something I bet most previous Temporal Agents didn't have, that would be a HUGE advantage in a Temporal War, if the enemies Temporal Effects don't fully work on you, or doesn't mess with your memory when they alter time.
They've shown that there are ways for StarShips to have Temporal Shields, but imagine what would happen is the people themselves who were critical to the fight couldn't be fully affected by Time Weapons or Time Effects.
That could be a game changer to the Temporal War.
And with the eventual bringing back of the Spore Drive & knowledge back to the mid 25th century of how to use it from the future along with a AI / Golem Paul Stamets to help with passing on knowledge from the future.
The end results of the Temporal Wars for the UFP and it's allies results in a win for the Allies of the Temporal Accord and the "Ban on Time Travel" never happens post 30th Century.
All Time Travel will get regulated as before, but it won't get banned.
Also "The Burn" won't occur because it'll be prevented from occuring and any SubSpace effects on Dilithium Crystals are now known and protected against.
It also becomes a new area of research on how Subspace transmissions could interact with objects in normal space.