At least 12 major U.S. cities have set homicide records this year, including topping five set just last year, ABC News reports.

The big picture: Experts cite fewer cops on the streets, reduced after-school and nonviolence programs, court systems that can't handle the strain, and mental health issues exacerbated by two years of COVID.

• "[I]t's worse than a war zone around here lately," Rochester police Capt. Frank Umbrino said after the city set a new all-time high on Nov. 11.

The bottom line: Minneapolis and Milwaukee are close to becoming Nos. 13 and 14 on the list.

Above: Instagram head Adam Mosseri pressed for industrywide solutions for protecting young users on social media as he testified before a Senate subcommittee.

• Mosseri highlighted research that found more U.S. teens are using TikTok and YouTube than Instagram.

Below: Crypto CEOs testify before the House Financial Services Committee as lawmakers debated how regulation should work for the emerging entities.

1. Canada and Australia announced diplomatic boycotts of the 2022 Beijing Winter Olympics. Full list.
2. Anthony Fauci told CNN he thinks it's "a matter of when, not if," the definition of "fully vaccinated" changes to include boosters. Video.
3. Pfizer and BioNTech said two doses of their vaccine were significantly less effective at neutralizing the Omicron variant in early lab tests, but a three-dose regimen was more effective. Go deeper.
4. President Biden signed an executive order requiring the federal government to achieve net-zero emissions by 2050. Go deeper.

Billionaire philanthropist MacKenzie Scott won’t be releasing a line-item list of projects this holiday season, explaining her reasoning in a Medium post:

How much or how little money changes hands doesn’t make it philanthropy. Intention and effort make it philanthropy. If we acknowledge what it all has in common, there will be more of it. That’s why I keep referring to what I’m doing as “giving,” a word still being used to describe what humans have been doing with their time, focus, food, cash, and trust to lift each other up for thousands of years.

It’s also why I’m not including here any amounts of money I’ve donated since my prior posts. I want to let each of these incredible teams speak for themselves first if they choose to, with the hope that when they do, media focuses on their contributions instead of mine.

The big picture: Back in June, Scott announced $2.7 billion in donations across 286 different organizations.

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