I don't think he's mentioned it specifically for each of the things in the checklist.

I'm pretty sure I recall him mentioning electric vehicles and solar cells being important for mars, but I don't remember the interview.

Elon and SpaceX have been pretty explicit about Starlink as a system for funding the development of Mars transit vehicles and initial colony, though I'm sure a mini-Starlink around Mars would be in the long term plans.

I don't recall anywhere that Elon Musk has mentioned anything about The Boring Company being used for tunneling on mars, but the connection makes a lot of sense to me, as initial colony development would probably take place largely underground as a cheap radiation shield.

It's not just that. The Boring Company wants to automate tunneling as much as possible (manual labour would be highly impractical in a spacesuit), speed it up and make it a continuous process. It also wants to power the boring machine by Tesla PowerPacks to remove the need for kilometers of cables. All of that seems suited not just for cheap tunneling but for Mars as well.

I guess mobile PowerPacks with solar panels? Just deploy a few thousand outside the tunneling area and then automate the battery switching. Could run it 24/7 without anyone ever going to Mars even.

That's how I understood. Instead of laying cables, the packs are moved back and forth between the charging site and the tunnel drilling machine.

It's a pretty natural conclusion people frequently arrive at. That said, I don't think it's valid, as I don't believe it was all explicitly planned like that. In particular:

1. Electric cars were created with Earth in mind. Musk was, and probably still is, very interested in ways to help fix the climate issue, and that reason was mentioned explicitly.

2. Connected to 1, not to Mars.

3. I'm not sure what the motivation here is; the official one was that Musk was bored ( :) ) in traffic. It meshes with Tesla's business if properly integrated. That said, the utility of tunnels for Mars settlement seems so big that I'm pretty sure he had it in mind too.

4. No colonies in a nearby future will need a Starlink-scale planetary Internet network. I'm 100% buying the official version here: Starlink exists to generate revenue for further work on the Mars transportation system/BFR (whatever its current name; Starship I think?).

I really don't think these were part of a grand plan all along. But they're all ultimately relevant for Mars.

There's a series of posts on WaitButWhy[0] about Elon Musk and his various companies and strategies. The level of Musk worship there generally rubs me the wrong way, but I think the conclusions are valid: the author also interviewed Musk one-on-one in 2015 and took a deep-dive into his businesses, so I would trust the author's conclusions. Essentially, Musk expects/worries that an extinction event (whether as a result of climate change, an asteroid impact, or whatever) will wipe out humanity on Earth, and believes that the best hope for our continued survival is to colonize other planets.

[0] https://waitbutwhy.com/2017/03/elon-musk-post-series.html

Over a decade ago, when Amazon wasn't the powerhouse it is today, I dated someone who routinely interacted with Jeff Bezos.

According to them, Bezos feels the same way. Amazon is basically a means-to-an-end, and that "end" is to get humanity into outer space, as an insurance policy in the event of a catastrophe on earth.

How come Bezos has never brought this up, ever?

Realistically, he's probably keeping a low profile because that's best for Amazon.

According to Bezos, Amazon is a means to an end, and that "end" is putting man in space.

If Bezos said something that spooked investors, that would be bad for Amazon, and what's bad for Amazon is bad for Bezos' long term goal:

Colonization of space.

Three week ago, Jeff Bezos said the following:

"But, Bezos said, if the Earth's population and energy consumption keeps expanding as it has, we will reach a point where every corner of the planet would need to be covered in solar panels to provide people with the quality of life the developed world has come to expect. "We will run out of energy on Earth," he said. "This is just arithmetic, it's going to happen ... If we move out into the universe, for all practical purposes, we have unlimited resources."

https://www.cnn.com/2019/05/10/tech/jeff-bezos-blue-origin-b...

He founded Blue Origin in 2000. For whatever reason, he is the opposite of Musk about his Space company - shares the barest minimum possible.

Given his support for The Long Now and Blue Origin it doesn't surprise me much.

http://longnow.org/

You’d think if they were really keen on that they would see the value of working together, not seemingly antagonistically, mind you competition is good, to an extent.

What I have noticed as that Elon uses metric, and Bezos Imperial units, Imperial units in space just seems stupid to me.

I came to the same conclusion by the way, so OP is not alone with this ;)

For SpaceX, yes, obviously.

For Hyperloop, he did too. And Hyperloop involve battery powered electric vehicles, tunnels and solar panels (on top). So indirectly, there is a connection.

He also made clear that colonizing Mars, or at least getting partway through is one of his life goals, if not his life goal.

There is definitely a connection. But following the progression, it seems like Mars isn't the reason he started these companies, but "how can I make it useful on Mars" is definitely a consideration.

What is special about 1, 2, and 4 specific to Mars colonization? Even 3. Like those things don’t even seem like the top of the list as the next things to tackle for planet colonization? (Is a Tesla the next important thing to tackle?) What about like food and environmental support since we can’t actually breath there?

This just sounds like some tortured narrative.

yes. https://www.inverse.com/article/34451-elon-musk-s-tunnel-pro...