I gotta admit that after reading the chapter on "Destiny has an Adventure" (which took almost a
month at three snippets a week!) I was all for avoiding storms and shoals and such, which the Silkiah - Thesmar canal enables shippers to avoid. Not that I still haven't pointed out that sea travel is 4-5 times faster and that a galleon can hold a
lot more than a barge, so other than the time wasted loading and unloading the ship, and the possibility that it might be lost at sea, shipping cargo by sea is a vastly superior method than dragging along at 50 miles per day on a canal. That is if you dare sail out of sight of land, which Charis has no problem doing, but the rest of Safehold seems a bit leery of even now.
I had a long, in-depth analysis of the Desnair/Siddarmark war that led to the CoGA stepping in and creating Silkiah as a buffer zone. Unfortunately it was eaten by the system while I was proofreading it, which just goes to show that I spend
way too much time proofreading.
So here's the Cliff Notes version. Siddarmark had already captured all of Silkiah and North Watch, and had Desnair trapped in Howard along a short, mountainous front, which it could have easily defended or even expanded well before Merlin showed up with innovations like rifles and artillery. However, some vicar with a lot of influence was probably rather upset that Siddarmark caused him to lose all the
lovely bribes he wanted to skim from the Salthar Canal, and Desnair was pretty upset about losing them too. So they basically did a Hanth and got the CoGA to intervene, a couple of
centuries after Siddarmark had seized the canal.
Now as the country with the biggest, nastiest army on Safehold, one would think that Siddarmark would have told the corrupt vicars to pound sand when the CoGA decided to not only set up a buffer zone between Siddarmark and Desnair, but to strip Siddarmark of its southern two provinces, hand one of them back to Desnair, and make the other an independent demilitarized zone. Silkiah was a province that Siddarmark had conquered two
centuries before, and losing it would have ticked Siddarmark off just a
wee bit, and had I been the Lord Protector, I'd have told Zion in which orifice it could stick their "treaty."
For perspective, this would be like some world court ordering the USA to return all its land to Great Britain, France, and Mexico, and the Indians.(Sorry, I refuse to be politically correct!) Once the country stopped laughing, we'd break out our 300 million guns and make sure it didn't happen! (Not to mention the world's largest military would laugh itself silly and say "Bring it on!")
Of course nobody had ever considered standing up to the corrupt leaders of Mother Church at that point, but exactly
who were the corrupt leaders of the church going to throw at the biggest and baddest army on the planet? Harchong? Please, the Siddarmark pikemen would have hacked and shot them into oblivion, and then the Church would have faced a major defeat after declaring jihad - which would have put them pretty much where they are now, with a failed jihad and the loss of face and belief in Mother church that goes with it. Had this occurred centuries before, with the added problem of a defiant Siddarmark refusing to hand over a land area almost as large as Dohlar that happened to have the Salthar Canal running right through it, the result for the CoGA would have been an unmitigated disaster! (Let's not forget to mention some major slave revolts in Harchong!)
By the way, if Shan-Wei built the Salthar canal, which I
firmly believe she did, I suspect that she made the locks bigger than those in the Great Langhorne Canal, since the Salthar would clearly carry more cargo eventually. So it may well have locks big enough to handle steam powered riverboats that a seafaring navy (cough - Chairs) might create with the purpose of capturing the canal (or working out a deal with the local potentate to use it) and happily sail any number of ironclads into the Gulf of Dohlar. Oh dear!
Since we know Shan-Wei founded Tellesberg along with St. Zherneau’s to encourage industry, she likely did that with the intention that her secluded, river-rich enclave would become not only a naval power out of necessity, but a trading power because of its distance from the Temple and relative freedom from the Inquisition breathing down its neck. (Until shortly before Merlin showed up that is...)
Had the CoGA simply left Charis alone, the war wouldn't have happened for at least another generation or two, and it would have been based largely on economics. Whether Charis would have survived is a bit of a toss-up, since it would have had a blue-water navy composed of galleons at that point, but without Merlin around to advance its artillery. OAR wouldn't have been nearly as much fun without a mustachioed seijin spurring innovation and doing acts of derring-do, but who's to say he wouldn't have shown up 50 to 70 years later than he did, which given the screwed up calendar, would actually have put his arrival much closer to the original date that Pei Shan-Wei intended, and closer to the date that the archangels are supposed to return. (As counted from the end of the War of the Fallen as RFC intended, not from the Day of Creation.) Big difference.
However, Merline would have had to choose between the biggest and the baddest who he'd basically make obsolete, or Charis, which was a naval power, but safe from any Church edicts because Zion would have had Siddarmark breathing down its neck to keep its corruption in line...
Changing the subject, Silkiah and Charis would have gotten along quite well, even if it were a province of Siddarmark, who would have very likely have been a very friendly mainland trading partner.
Of course all of those Charisian cargoes were going to need markets, and being able to cut off 20,000 miles from a voyage to the Gulf of Dohlar would be significant. That's one of the major reasons that Charis and Silkiah got along so well - Charis was undoubtedly doing a great deal of transshipping through Silk Town via the Salthar Canal, where coasters would pick up their cargoes at Port Salthar on the west side of the canal and deliver them to ports around the Gulf of Dohlar, and even a small coaster could sail as far as Harchong faster than a galleon could circle all of Howard, and do it more safely.
The reverse worked as well, although I'll admit that setting up a coaster to pick up cargoes in the Gulf of Dohlar to deliver to Port Salthar would be more difficult, and run the risk of one's cargoes arriving late, or arriving early and spending some time waiting in a warehouse after being shipped across the canal to Silk Town, but the semaphore was available, and before the jihad, Charis was creating some very large shipping houses. The relationship worked well until the SoS showed Silkiah what would happen to it if it kept accepting Charisian cargoes, but had Siddarmark told the CoGA to pound sand when presented with the Treaty of Silkiah, which in essence stripped it of its southern two provinces to the benefit of Desnair, the CoGA would have found itself not only defied, but unable to do much about it.
Yes, Siddarmark has a large percentage of TLs, but in this case, the government, which controlled a large part of the semaphore network could easily have spread the word that the Treaty was merely a grab by the corrupt vicars to skim profits off the canals. Since those venal men would have been sent from areas far from Silkiah, I doubt they were generally beloved or even much tolerated in Port Salthar and Silk Town. They'd have found themselves aboard a coaster with all the loot they could carry while their palaces burned behind them.
It simply came down to not having a Lord Protector willing to say
"Here I stand, for I can do no other!" Fortunately both Charis and Chisholm
do have rulers like that... and they're showing what modern weapons can do to a united Church offensive, when Siddarmark could have destroyed a similar offensive two centuries before if it had simply had the guts to stand up to the Church.
An added benefit to such a policy would have been the elimination of the Border States, the seizing of the Great Langhorne canal, and Siddarmark sitting on the Temple Land's eastern border, making sure that the CoGA behaved - or else!
An official policy of refusing to accept church edicts that were purely political in nature would have done Siddarmark and all of Safehold a great deal of good, and would have kept the corruption of the church to a tolerable level, since Siddarmark could always have swept up the Temple Lands if faced by armies without rifles or artillery, and the Church was clearly fearful of facing Siddarmark without the buffer of the Border States. Too bad Siddarmark didn't have a Lord Protector with some guts back then, because its army most likely
would have accepted orders that contradicted purely political orders from the CoGA, and its million troops could have created a relatively corruption free-state. (No state is corruption free of course if humans are running it - just look at the changes in the USA in the past 15 years!)
But Siddarmark isn't Harchong with an entrenched bureaucracy so corrupt that any bribe large enough can get the local inquisitor, government official, or dog catcher to look the other way. Siddarmark doesn't have slaves, so the Temple Lands would have been in
serious trouble had a Siddarmarkan pike army come calling to free its land-bound "serfs," and eventually Zion would have found itself with a fairly antagonistic Siddarmark that entirely surrounded Lake Pei, controlled the entire semaphore network coming out of Zion, and would in effect have made Zion's political influence negligible, since the threat of a Siddarmarkan invasion if it got too upset by the Church's decisions would always loom over the vicar's heads.
It wouldn't have been the world Merlin wanted, and he'd have probably planted his "virus" in Siddarmark rather than Charis, but he'd have also been in position to capture Zion and the Temple if they didn't cave to what Siddarmark demanded. Plus with so much of Safehold already under Siddarmark's banner, (I doubt they'd have been idle in decimating Desnair during those two centuries) the Big Reveal would be a lot less violent. Sure the slaves in Harchong could riot (good luck with that!) and the sheepherders in Sodar might be upset, but other than Dohlar, which might well have been swept up by Siddarmark as well, who would be left to object? (Keep in mind that Siddarmark with a population of at least 300-400 million with that amount of expansion would have
no problem destroying
anything Harchong or anyone else threw at it.) Desnair may have already fallen to Siddarmark, along with a large part of Howard, plus Siddarmark would probably have a fairly large fleet of coasters and galleys in the Gulf of Dohlar just in case Harchong felt adventurous.
So the Church's worst nightmare would have come true - an expansive Siddarmark parked on its doorstep, keeping it in line politically, and occasionally telling it to go pound sand or it would pound a few vicars!

All it lacked was a Lord Protector with the guts to stand against Mother Church - but two centuries ago, there wasn't much chance of that, even though the Treaty of Thesmar would have been unenforceable had Siddarmark simply refused to sign it.