As America grapples with the #MeToo movement tidal wave, Rebecca Traister's new book, "Good and Mad: The Revolutionary Power of Women's Anger" (Simon & Schuster, 252 pp., ★★★ out of four) serves as an "Amen, sister!" venting session.

Traister hits pause on current events to explain what's fueling the rage and assures the reader that it's OK to be angry.

Any book that mentions a brank – also known as a scold's or a witch's bridle, a muzzling torture device from the 1500s put on women's jaws to prevent them from talking, sometimes with a spiked metal tongue depressor – isn't going to mince words. Red-hot emotions seep out from the black type on the page. You can practically hear Traister striking each letter on her keyboard like a Kermit GIF.

Here are five takeaways from "Good and Mad":

1. The Trump era is inspiring activism.

American women have not only grown irate post-Trump, but they've taken action. Yes, there was the Women's March, but they've also turned out in droves in – not just at –ballot boxes. The number of women running for political office has skyrocketed, and political activism workshops are jam-packed.

Traister points out that four female judges initially stayed Trump's travel ban and that the irate mayor of Hurricane Maria-ravaged San Juan, Puerto Rico (Carmen Yulín Cruz) and the U.S. senator who coined the phrase "Cadet Bone Spurs" about Trump (Tammy Duckworth, D-Illinois) are female.

2. When an angry image is damaging.

The Internet is filled with photos of powerful women, especially politicians, looking angry, and that serves to not only portray them and their behavior, not matter how justified, as ugly but to deter such emotion, Traister writes. Women may see those images – "with their mouths open, unrestrained: mid-yell, spittle-flecked, the very act of making a loud noise a sign of their ugly and unnatural personalities" – and think twice about emulating them.

3. Is white anger more acceptable than black?

The stereotype of the angry black woman makes it even harder for women of color to express their outrage, Traister argues. That ranges from criticisms of Michelle Obama (remember that New Yorker cover?) to the belittling of Rep. Maxine Waters and her, in the words of #MeToo-tanked Bill O'Reilly, "James Brown wig."

4. The historical roots of female anger.

Traister touches briefly – too briefly – on this point with mentions of key labor organizer Mary Harris Jones, aka Mother Jones; union organizer Ella Reeve Bloor, who helped Upton Sinclair with "The Jungle"; Mamie Till, who insisted the mortician keep her son Emmett's coffin open so the world could see how brutally he was murdered; the drags queens and lesbians at the center of the Stonewall riots; and a weeping Gloria Steinem at the 1972 Democratic National Convention when presidential nominee George McGovern double-crossed the feminists present, including presidential aspirant Shirley Chisholm, by failing to advocate legalizing abortion.

5. And it wasn't always pretty.

One of the best examples of the positive outcome of women's anger, Traister writes, was the suffrage movement, but a racist thread ran beneath it. Many women fighting for the right to vote were angry when, after the Civil War, black men were granted suffrage before they were. Elizabeth Cady Stanton was particularly vocal about it.

Follow USA TODAY reporter Zlati Meyer on Twitter: @ZlatiMeyer