None of this behavior is a surprise to the right. The left more than a decade ago began embracing intimidation as a basic political tool. Think of the Internal Revenue Service targeting conservative nonprofits, or Barack Obama browbeating the Supreme Court, or activist boycotts of companies that supported Republicans. By giving license to this behavior, senior Democrats allowed it to escalate dramatically in the Trump years. Remember Rep. Maxine Waters cheering when White House press secretary Sarah Sanders was run out of a restaurant and telling followers to do the same to others, to “create a crowd” and “tell them they’re not welcome anymore, anywhere.”

It’s also no surprise given the cover Democrats and the media gave to appalling behavior over the past 18 months. What’s to stop bullying or harassment (much less looting, rioting and arson) when the media and Washington elite will consistently and helpfully write it off as just a bit of “peaceful protest”?

There are small signs Ms. Sinema might be wearying of the treatment and moving more decisively to get on board with reconciliation. Progressives will take that as validation of their ugly campaign. Yet Democrats should be very worried about where this ends, not only for the country, but for their own party.