Do we know who actually put Orion into the bill? Giving some Texas or Colorado Senator other priorities seems like a much better approach than messing with Hatch.
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I don't think it was 'explicitly' re-started it was just generally assumed that the SLS would need to carry government passengers in something so Orion was there by de-fault. It's essentially the whole underlying 'reasoning' that "Commercial" wasn't actually going to BE commercial because the customer was going to be the government anyway. That the commercial efforts were going to out-pace the government one was something that you'd think would have been obvious but apparently wasn't. So you have commercial vehicles flying before the government one by the simple expedient that the government LV has little incentive to fly while the commercial ones actually do.
And so here we are. The only reason I suggested Hatch is he's low-hanging fruit as ATK/Thiokol had plenty of other lobbyist but the Utah delegation is always going to be the front runner. Having the folks from Alabama and Florida (LRB lobby) being more organized and willing to take up the fight earlier could delay the full SLS authorization but I'm not sure how you don't get funding for Orion in most cases because as I said it was kind of assumed by everyone from the start.
If there is a government designed and built LV it will have a government designed and built crew vehicle on it, is essentially just a continuation of how the US program , (and frankly all the government programs) has always been run. I get the feeling, seeing all the comments about the "commercial" lunar lander program that far to many people don't understand it's NOT what most of them think it is. While it IS actually very different than what's been previously done by NASA it's not that different than any other government funded vehicle development program in that the end use is still going to be the US government, not a commercial entity. (Some people get rather outraged when I point out that if the US government pays for SpaceX to build a Lunar Starship then the GOVERNMENT, not SpaceX is going to operate and control it
)
Too many people think the government is planning on using Dragon, (and eventually Starliner) as the main transport to and from orbit and that's true to an extent. But the OFFICIAL position is that these are actually backups for SLS/Orion and not the other way around. To get Orion dropped for good you pretty much have to lose SLS, and even then it's likely without a clear mandate from Congress it will probably still be kept on life-support with the aim to use a "commercial" booster to launch it.
You're very correct that the early 'teens' of this century is/are/was a pivotal point, the problem is we HAVE been pivoting and quite radically in some ways compared to before
Getting any MORE of a radical change is tricky.
Another thing I'll bring up is something you said in that:
For context, I had been figuring that while Orion is cancelled, SLS still happens (pretty much explicitly because I didn't want to mess with elections in Utah), and the plan is essentially to use the SLS like Ares V (uncrewed), and replace Orion and Ares I with commercial vehicles launched on a commercial LVs. So the justification is that all the commercial "exploration" vehicle actually has to do is simply ferry government astronauts to a departure stage in LEO, so really it's not that different from commercial crew.
The split between Ares V and Ares i was artificial and frankly not well supported by either NASA or Congress (except for specific and very focused reasons on both sides, go figure, politics is complicated
) because it was very different than any NASA planning for expanded missions. Obviously since it was originally supposed to JUST be the Ares V doing Mars Direct-type missions. The Ares 1 got added in to support orbital operations and the ISS, which again NASA in the form of Griffen was opposed to but Congress insisted. Constellation as a whole was not supposed to even do anything in orbit and would only visit the Moon to verify the hardware for Mars, (If that) so an orbital crew vehicle made no sense. Congress thought otherwise so Ares 1 came about and was justified with splitting the crew from the deep space payload. Piled on top was the basic NASA aversion to split missions and orbital infrastructure building which is pretty institutional (yet oddly also a constant concept with NASA) if they can do an "Apollo" type program instead and I suspect you can see why Orion went from Ares 1 to SLS so easily.
This is especially a problem with SLS/Orion because it was rather obvious that SLS wasn't going to be anything on the level of the Ares V even with the 'mandate' inserted by Hatch and company.
Something to keep in mind is that the payload was specified NOT for any mission requirements but to ensure that SLS would use SRBs. Period. LRBs would arguably be cheaper and more efficient but essentially Hatch-et-al were 'assured' by "experts", (no prize for guessing who they were
) that the given payload could only be lifted by SRBs and therefore that's what was required. Nobody really cared how much the actual payload of the SLS was going to be, only that it could carry Orion to orbit because that's all anyone actually figure it would ever do anyway. "Commercial Cargo/Crew" was simply seen as a way to keep the complaints down while SLS/Orion meandered its way to operation and frankly I see Congress and NASA, (and more the former than the latter) as being caught flat-footed that it has done as well as it has. NASA seems to be adapting but Congress in the end will always have the purse stings so it remains to be seen how far they'll let it go if it should directly threaten SLS/Orion.
Having Congress being too busy in-fighting over SLS/Orion may be the best possible way to get where you want to go but I'm not sure how much such fighting would end up effecting Commercial Cargo/Crew.
Randy