I'm not surprised that Bill Gates remains optimistic that we can avoid ecological disaster despite little progress toward reducing carbon emissions. But I am a bit surprised he won't take a tougher public line against President Trump.

Gates has met several times with Trump, most recently in March. And while he has yet to get concrete positive action from the president on climate or other issues close to his heart, he refuses to talk critically about the president.

Pressed several times on the matter in an "Axios on HBO" interview, he briefly acknowledged areas where the executive branch hadn't taken action before quickly shifting to point out others who have acted — including Congress, business leaders and other countries.

Why it matters: In his post-Microsoft life, Gates has emerged as one of the world's biggest philanthropists, focusing on global health and other issues. Many of those benefitting from Gates Foundation investments are also those feeling the impact of climate change most severely. Gates has also been an investor in a number of energy projects, including Terrapower, a small-scale nuclear energy startup.

Between the lines: Gates isn't alone among tech leaders. While some are clearly outspoken critics, others have preferred to either pick their battles or otherwise work with Trump even as they oppose his positions.

• Apple CEO Tim Cook also continues to meet with Trump, even as he opposes a number of the president's policies, including his positions on environmental issues, immigration and LGBTQ issues.
• In addition to being an eternal optimist, Gates is also highly pragmatic. Evidently he has concluded there just isn't enough to gain by publicly criticizing the president.
• My thought bubble: While tech CEOs have to consider their fiduciary duty to shareholders in weighing how much to confront Trump, Gates is freer to take a tougher line if he chooses. Trump seems to crave approval and playing hard to get might be an effective tactic.

The big picture: Gates did talk about the challenges that make this a tough issue, broadly speaking, on which to summon political will.

"It's not an easy problem to engage people in because the effects come just gradually," Gates told Amy Harder and me in the interview. Plus, he says, the problem is complicated. People tend to focus on transportation and clean energy, but that's only a small piece of a much larger problem. (Amy Harder has more on this in her column.)

The bottom line: Gates said there is a fundamental unfairness in the impacts of climate change.

• The rich will be disappointed on vacations: "Our visits to coral reefs won't be as nice as they've been in the past."
• But the poorest will starve: "The people who didn't do the emissions are the ones who will will suffer the most," Gates said.

Although he frequently warns about the dangers of artificial intelligence, Elon Musk is also betting big on the marriage of man and machine.

In addition to his better known work at Tesla and SpaceX, Musk is backing an effort called Neuralink to help people download and eventually augment their brains. The idea is that you would be able to get an implant that would allow you to do processing of information in the cloud that could then be downloaded back into your brain, thanks to implanted electrodes and wires.

"The long term aspiration... would be to achieve a symbiosis with artificial intelligence and to achieve a sort of democratization of intelligence such that it is not monopolistically held in a purely digital form by governments and large corporations," Musk said in an interview with "Axios on HBO."

The bottom line: Musk believes the singularity is inevitable. "It's like it's not clear whether it's going to be good or bad," he said. "But it's something that's unknown and likely very difficult to control."

Go deeper: There was plenty more Musk said during the interview.

• Of all the big tech companies, Musk said Amazon comes closest to being a monopoly."It's hard to think of a good you know a serious competitor to Amazon.... I mean who's number two? Walmart maybe?"
• Musk thinks there is a 70% chance the technology will be ready for him to make a trip to Mars.

Apple will be before the U.S. Supreme Court this morning as part of a long-running dispute over whether the company exercises and abuses monopoly power in being the sole distributor of iPhone apps and taking a 30% cut.

Why it matters: The ruling could impact a broad range of digital marketplaces, not just Apple's. The company has seen support for its position from a range of tech and business trade groups, including ACT Online, CCIA and the Chamber of Commerce.

Between the lines: The Supreme Court isn't deciding the merits of the matter, but rather deciding whether those who buy iPhone apps can sue the company over the way it runs the App Store and takes its cut.

• What Apple will argue: The iPhone maker believes that if anyone has a beef with the company, it would be developers, not consumers. Furthermore, it believes that by serving as an intermediary it is making the iPhone environment safer while still allowing developers to set their own prices.
• What the plaintiffs maintain: Lawyers for the consumers suing Apple contend that the business relationship is between Apple and consumers. After all, it's Apple that shows up on your credit card when you buy apps.

The bottom line: It's an important case as more and more of the economy shifts from physical marketplaces to digital ones, and one more way in which the antitrust argument is being made against big tech.

Over the weekend, the U.K. Parliament seized internal Facebook documents in an unusual move aimed at answering questions it feels the company has been dodging, the Guardian reports.

The big picture: As Axios' Sara Fischer reports, the move comes amid mounting pressure on Facebook CEO Mark Zuckerberg to testify in front of the members of Parliament and other world leaders for weeks, but Zuckerberg has repeatedly turned down such requests.

Details: The files reportedly contain "significant revelations" about Facebook decisions on data and privacy control, as well as correspondence between top executives, per the Guardian.

• But the story of just how Parliament got the documents is a fascinating one, no matter what the papers actually show.
• Damian Collins, chair of Parliament's Digital, Culture, Media and Sport Committee, invoked a rare parliamentary mechanism to force the founder of a U.S. software company to hand over the documents while on a business trip to London.
• In a dramatic and unusual move, a sergeant at arms was sent to the founder of Six4Three's hotel and ordered him to hand over the documents or face fines and, potentially, imprisonment, according to the report.

Background: Facebook has faced pressure to be more transparent with officials around the world, and particularly in the U.K. and EU, over how it handles an array of issues, like data privacy, election meddling and terrorist content.

• On Friday, The Washington Post reported that Zuckerberg declined to testify at a rare joint hearing with lawmakers from seven countries, including Argentina, Brazil, Canada, Ireland, Latvia, Singapore and the U.K.
• Lawmakers had been lobbying Facebook to appear for weeks, even launching a Twitter campaign to get people to retweet their plea to have Zuckerberg testify.
• Facebook will be sending Richard Allan, vice-president for policy, in Europe, the Middle East and Africa, in Zuckerberg’s stead, as confirmed by the Washington Post and TechCrunch.
• Last week British members of parliament urged advertisers to boycott Facebook and Google over their alleged inability to contain terrorist content.

Be smart: It's unusual for countries from four different continents to band together in an effort to hold a U.S.-based company accountable for its actions in this way. The move suggests that Facebook's public relations crisis in the U.S. is spilling over globally.

The bottom line: Facebook's year of controversies in the U.S. might be the beginning of many more to come abroad.

On Tap

• Amazon's AWS Re:invent takes place in Las Vegas

ICYMI

• Amazon's arrival could worsen D.C. housing crunch. (Axios)
• How a Trump tweet gets made, per an insider. (Axios)
• Wireless data prices in the US are among the highest in the world. (Motherboard)
• Logitech said Sunday it has broken off talks to acquire Plantronics, following earlier reports the two were in discussions. (Reuters)
• Chinese scientists are said to be creating babies whose genes have been edited using CRISPR. (MIT Technology Review)

Trading Places

• Dave Stephenson is joining Airbnb as CFO. He was formerly at Amazon.

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