The biggest threat to the Trump presidency, the markets and our ability to deal with future crises is the coming staff exodus. We cannot stress enough how many essential staff and officials want out — if not this quarter, then soon after the new year:

• Watch for Gary Cohn to bolt after tax reform, which we think slips into Q1 of 2018.
• Secretary of State Rex Tillerson's situation is untenable: We hear he's likely to leave by the new year. Many insiders think U.N. Ambassador Nikki Haley will replace him. Then Deputy National Security Adviser Dina Powell may take Haley's job in New York. Another possible successor in case of a Rexit: CIA Director Mike Pompeo.
• Chief of Staff John Kelly is the one to watch closest. He doesn't get enough credit for the discipline he has enforced inside the White House. He bristles at the boss's loose, erratic ways, though. The average tenure of a COS who likes his job is roughly a year. A weak chief of staff replacing Kelly would be hugely problematic.

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The most important non-Trump story of the year is the rising clash between Washington and Big Tech — Google, Facebook, Microsoft, Apple, Amazon and even Twitter. We think this ends with some kind of new regulations and/or legislation. The only question is how severe.

At least two tech companies — Facebook and Twitter — will testify before Congress to explain the spread of misinformation on their platforms. Specifics to watch:

• The companies will be pressured to make some major changes in how they monitor political ads on their platforms, and where they're coming from.
• Congress will eye new rules on disclosure to bring political advertising transparency in line with rules for TV ads.
• Though some are pushing for measures to regulate the big tech platforms — possibly through scrutiny over concerns of anti-competitive practices, or rethinking antitrust laws for the digital age — full-on regulation is highly unlikely. For now. —Kim Hart.

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Media companies, for the first time ever, feel they have leverage in their fights with Facebook and Google:

• Media and advertising powerhouses like WPP's Sir Martin Sorrell, News Corp.'s Rupert Murdoch and Procter and Gamble's Marc Pritchard have all become more vocal about their gripes with the duopoly. They want a bigger slice of revenue and more access to their data.
• We hear numerous publishers and industry leaders are in discussions to apply collective pressure on the companies.
• Watch for very aggressive reporting on the flaws of Wild West platforms, on one hand. And for companies to invest even more in competing platforms and tech, on the other. —Sara Fischer

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Republicans are done trying for repeal of the Affordable Care Act. Watch for Trump to move quietly to keep the health care markets from crumbling:

• What's next: As open enrollment begins, real people will begin to see the real-world effects of major premium increases and limited competition. The Trump administration will have to decide whether it wants HHS to make those problems worse, which would help make the case that the ACA is a failure, or to ameliorate them.
• Congressional leaders from both parties will have to decide soon whether they want to try to stabilize insurance markets for the next few years.
• Keep an eye on BernieCare: Democrats are moving fast to back a single-payer system, a much more expensive and politically dangerous plan than Obamacare. We believe this become a new litmus test for Democratic presidential hopefuls. —Sam Baker

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Watch to see what, if anything, can slow the dizzying climb of company values. Not just the Fortune 500, but also privately-held giants like Uber and WeWork:

• Markets are in the midst of their second-longest bull run in history. When something does cause things to turn — whether through policy or external event — the displacement can be severe.
• Remember, an entire generation of workers knows nothing but unicorns and rainbows.

What's next:

• In D.C.: Who gets picked for next Fed chair? What happens to tax reform? Will antitrust regulators OK the AT&T-Time Warner merger? Is any action is taken on corporate inversions?
• On Wall Street: Will Spotify upend the IPO market via a direct listing? Will private equity firms continue their record fundraising? Has passive investing peaked?
• In Silicon Valley: Can Uber get back to business? Will the VC glut begin to shake out? Will the next mega-startups be in biotech instead of IT? When will companies like Airbnb bite the bullet and go public? —Dan Primack

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The nation's insane spike in opioid addiction is creating a crucial — and overlooked — job shortage. We have 1.7 million people who are jobless and not looking for work, many as a result of addiction:

• Company and industry executives tell us that they often cannot fill job openings because applicants can't pass a drug test. So houses go unbuilt in Dallas, oil undrilled in the Permian Basin, and manufactured metal products unmade in Ohio and Pennsylvania.
• What's next: Executives say that if jobs continue to be unfillable, automation will be accelerated — the trendline that has fueled mass joblessness in U.S. manufacturing and rust belts, as well as the politics that polarizes us. —Steve LeVine

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One of the most fascinating trends in regulation is growing concern among energy execs that Trump is rolling back too many regs, too fast. Many CEOs want certainty more than short-term rollbacks:

• What's next: The United Nations climate summit, held this November in Germany, will offer the most explicit chance for the administration to lay out its plan on climate change. Ironically most CEOS want Trump to listen to Gary Cohn and revert to the Obama status quo. —Ben Geman and Amy Harder.

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Watch science push us into unexplored and sometimes disputed territory:

• Gene editing was recently carried out in human embryos. We'll be watching for follow up studies, research on the accuracy of the DNA-snipping tool CRISPR and the ethical lines being drawn.
• Immunotherapies: Researchers want to know why tumors in some people are susceptible to the drugs and others are not.
• Planets — near and far: Cassini is gone but scientists are still making their way through the probe's data so we'll be looking for news about Saturn's moons, two of which were found to have ingredients for life. Juno, in orbit around Jupiter, will likely return new photos of that turbulent world. And if we're lucky, we'll get some news about the elusive Planet 9. —Alison Snyder

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