https://arstechnica.com/science/202...ering-146-million-for-each-sls-rocket-engine/ The dumbest thing is that these engines are designed and proven for reuse (they're rebranded Space Shuttle Main Engines). And they're just going to drop 5 of them in the ocean every launch.
Part of the reason for the expense is that there are so few SLS launches forecast that all the tooling and research costs are spread over a relatively small number of engines, whereas SpaceX is going to be cranking them out due to the number that Starship requires. It's still insanely expensive by comparison though, and there's a chance of SpaceX launching a crewed Super Heavy launch before the first crewed SLS launch and majorly embarrassing them. Some interesting speculation I saw was that NASA including SpaceX on the lunar lander planning contracts could be one way of getting around congressional bans on NASA doing any work regarding orbital fuel depots. The main advantage of SLS isn't the size of the payload it can launch, but the mass it can launch in one go. Orbital refuelling would allow much cheaper launchers to perform many of the tasks SLS is slated for at a fraction of the cost. Interestingly, most of the SpaceX Starship plans also rely on orbit refuelling...
You can thank crony capitalism as much as you can thank the government. The SLS was originally was going to cost a lot less, then one of NASA's directors (I think he was appointed by Bush, but it might have been Obama) changed a whole bunch of stuff because he wanted to keep certain government contractors happy. (I believe that these were all ones located in states with key members of Congress who have oversight of NASA.) If they were happy, then he could count on them to continue to lobby Congress to keep funding NASA. Really, though, it isn't anything different than what happened with the Apollo program. LBJ knew that if he wanted to get the program going (and keep NASA around), he had to make sure that there were NASA facilities scattered around the country, so Congress Critters would continue to fund the program. Launch control is in Florida, but Mission Control is in Houston. Makes no sense. There's logically no reason why it all can't be done from Florida. But if you put part of it in Florida, and part of it in Houston, then you have more members of Congress willing to support the program, even if they don't understand WTF it does or why it's so important that it does things. Didn't you ever wonder why NASA does its test firings of new rockets in Utah? Doesn't make any sense, and limits the sizes of the rockets that can be designed to the width of the railroad tunnels and overpasses between Utah and the various launch sites. But it ensures that members of Congress from Utah will continue to support NASA. It would be nice if we lived in a world where people recognized the value of science and didn't have to be bribed into supporting it (we'd certainly be able to get a lot more science done, for the same amount of money we're spending now), but we don't. As a result, we have to do things like this to get valuable agencies enough funding to do anything. One needs to only look at how the CDC has been treated in recent years to see how little respect many of those in power have for the sciences. ETA: Said director went on to get a job at one of the big contractors after he left NASA. And yeah, they did make a lot of money thanks to him.
This is why companies like SpaceX are a good thing, and the way to go in the future. Anything the gub'mint can do, private industry can generally do better and more efficiently.
I'm guessing (just a hunch) that they didn't consult Paladin before they decided to buy these. That said I think COSTCO carries these engines in bulk - if the COVID panic buyers haven't picked them clean!
There do seem to be countries with lower interest taxes than the USA: https://www.cnbc.com/2018/03/02/countries-that-pay-less-in-taxes-than-the-us.html (no time to vet the list myself right now)