Why do people claim that the Empire is working a long term plan in the aftermath of the White-Gold Concordat (WGC)? I'm serious; why?

Long term planning is characterized by forgoing a profit/benefit in the immediate future in the interest of gaining a larger return for ones investment in the more distant future.

Short term planning is characterized by forgoing a profit/benefit in the more distant future in the interest of gaining profit/benefit in the near future.

"Immediate future" and "distant future" are not terms easily defined by counting years. Any argument along the lines of "25 years has passed, therefor it is long term" will be ignored as irrelevant to the discussion, because it is.

I am starting from the assumption that the Emperor, the members of the Elder Council and the Imperial Generals are not complete morons. Irrespective of whether or not the Empire is in the right, I think it is a fair starting point to assume the Empire's leadership has, at the very least, an understanding that undermining and selling out ones allies will shorten their list of reliable allies. So I'm excluding the answer of "it was intended to be a long term plan, but it didn't work out". This is simply because I think that if you think the Empire's leadership are so incompetent that they thought that signing the WGC was "long term" thinking in light of, well, the WGC, there isn't much to discuss. You should have ample reason to dismiss their leadership qualifications on that alone, because that would simply be detached from reality.

Note: This is not a thread about "what the Empire could/should have done". What I am about to point out is a rough sketch of what I would expect to see if the Empire approached this with the long term in mind.

Looking at the situation of the Great War, I would say that the most obvious case of "larger returns for ones investments" would be not splitting the Imperial Provinces apart. If one can unite all 4 Imperial Provinces in the fight against the Dominion, and avoid certain stipulations that target the Empire's allies. Not having to cecede land in Hammerfell and not having to agree to ban Talos, because these are the most obvious trouble-makers in the WGC, would probably have cost the Empire then and there, because the war would not end in 4E176.

This does carry some risks, like losing the war, and the damage done potentially being higher than the benefit one would reap, but the general idea is to not give the Dominion these stipulations that does hurt the Empire in the long term by 1) outright splitting Hammerfell from the Empire on bad terms, and 2) create a significant amount of strife between the Empire and Skyrim, which is disproportionally affected by the Talos ban. Refusing to sell out their provinces has the potential benefits of strengthening the loyalty to the Empire, since it stood up for them, and that you do not lose the manpower and resources in the provinces. Nor do you have to spend ressources dealing with the result of the strife, which in this case would be the Skyrim civil war in 4E201.

As Daniel Dennet once said: "Every time one reads or hears something, one makes a mental copy of it. Every time one reads or hears something, one makes a mental copy of it." In light of that I will repeat that I am not putting this scenario up as what "should have been done". That is not the topic of this discussion. This is strictly an example of how one would approach the situation with a long term goal in mind based on the assumption that the Empire's leadership is not so incompetent that they could not foresee the Redguards and Nords (and possibly others) taking serious issue with the WGC.

What actually did happen at the end of the Great War?

The Empire ceceded land in Hammerfell to the Dominion, which resulted in the Redguards objecting and subsequently being denounced as an Imperial Province to stand on their own against the Dominion, and accepts the Talos ban, which creates increasing anti-Empire sentiment in Skyrim, which is the most affected province regarding said ban. This resulted in the Skyrim civil war.

As we see with the Dark Brotherhood questline in Skyrim, the situation has also created dissidents willing to go so far as to assassinate the Emperor in the Elder Council. Whether this is due to the influence the Thalmor gained (Amaund Motierre being a traitor) or the weakening of the Empire (Amaund Motierre being a patriot) is unknown, due to little to nothing being known about the goals and affiliations of Amaund Motierre. The point is that it shows that there is also creating strife in the Elder Council to sign the WGC, which is where the weakening policies and the Thalmore influence both come from.

I will reiterate that I do not believe the Empire's leadership to be so detached from reality that they did not see these problems being very real risks when signing the WGC.

Why did they sign the WGC? Simply put to end the war quickly so they could begin to rebuild their armies and attack the Dominion.

As I believe the Empire's leadership must have understood that signing the WGC would alienate at least 2 of their provinces and some members of the Empire's leadership, placing the seeds for strife and rebellion, this can only be characterized as an arms race. This is the Empire trying to beat the Dominion before the house of cards that the Empire became under the WGC collapses on top of them.

Agree or disagree with the Empire, this is short term planning. Not long term.

TES Legends recently gave some new revelations of the events of the Great War, revelations that I believe shine some light on why the Empire would agree to the Concordat. We now know why the Dominion had such success in Cyrodiil- Lord Naarifin used the Orb of Vaermina to spy on the enemy armies, and was accompanied by a Dremora champion of Boethiah. Ultimately, he lost the orb, he lost Goldbrand, and soon after, his entire army was wiped out. In other words, the only reason the Dominion was so successful in Cyrodiil was that they had extraplanar trump cards. The Empire was in no shape to go onto the offensive, and so may have agreed to peace in order to rebuild, with the logic that without their Daedric artifacts and the element of surprise they had last time, they would not prove as challenging a foe the second time.

As for the topic of Hammerfell, they rejected the peace that the Empire's leaders wanted to agree to, and the Empire gave them what they demanded- a continuation of the hostilities. Would you rather the Empire forced Hammerfell to comply with the Concordat? And it was not a complete loss for the Empire- as an independent nation, Hammerfell continued to bleed the Dominion for five more years, ultimately removing all Dominion presence in Hammerfell without the Empire having to lift a finger. This did have the effect of causing tensions between Hammerfell and the Empire, but the Redguards served their purpose- a purpose that they chose for themselves when they refused to agree to the Concordat and demanded to keep fighting. And when tensions brew up again, only a fool would let their grievances with the Empire get in the way of ensuring that the Dominion doesn't get another chance to attack Hammerfell, which they will if Cyrodiil ever falls.

Skyrim was even less of an issue at the moment- the civil war was the end result of Thalmor manipulations going back to before the Markarth Incident, for the purpose of bleeding both Skyrim and Cyrodiil- and possibly for the purpose of having an excuse to more actively hunt down Talos worshipers in Skyrim, all the while more and more Talos worshipers would die in the civil war. The Empire's leaders could not have foreseen that the Thalmor would orchestrate a civil war over the Concordat's terms, which are ultimately temporary until the war between the Empire and Dominion resumes- which Ulfric seems to think will never happen.

Finally, there may be one more thing to take into effect- White Gold Tower. Given Naarifin's plans to summon Daedric reinforcements through a sacrificial ritual, and the fact that he waited until he captured the Imperial City before setting it in motion, it's possible that he needed to be in control of White Gold Tower in order to do so. If so, then Cyrodiil's position as the center of the mythic wheel remains vitally important, and by agreeing to the Concordat, they ensured the Dominion would no longer be within striking distance of the Tower.

In short, I believe the reasoning was that even with the loss of Hammerfell, the Dominion lost even more potent advantages, and would continue to spend money and lives fighting the Redguards. The Dominion's seeming inability to hold onto their territorial gains in Hammerfell only served to hammer the point home (pun intended) that they would not be as militarily potent a foe a second time. Their sabotage efforts in Skyrim and lack of desire to see a Stormcloak victory may only further reinforce the idea that they're a paper tiger. And even if the Thalmor have not completely lost the favor of their Daedric patrons, the Empire now knows what they may be up against.

It is true that the Concordat allows the Thalmor to openly operate in Imperial territory, but I do not doubt that the Penitus Oculatus are hard at work gathering intel of their own in Dominion territory, something they probably weren't doing back when the Dominion showed no signs of being an enemy. And while there is no proof, I speculate that the Dominion's abrupt and seemingly improbable success in identifying and wiping out the Blades was not simply due to superior intelligence, but from Naarifin's Daedric resources. The timing and flawless execution after years of the Blades successfully sabotaging them seems too perfect to be attributed to mundane competence.