American history is, in many ways, a story of grand protests. They generally come in two types.
There are protest movements that, even in ferocious dissent, believe that the American system is ultimately geared to fulfill its inner promises – of equality, unalienable rights, the pursuit of happiness, e pluribus unum, a more perfect union.
And there are protest movements that have turned against the system, either because they don’t think the system can meet its promises, or because they never agreed with the promises in the first place.
The experience of nearly 250 years is that the first type of movement generally succeeds: emancipation, suffrage, civil rights, marriage equality. They have aimed to build the country up, and bring Americans more closely together, on foundations already in place.
The second type – from the Confederacy to the white supremacy of the Jim Crow era to Black nationalism in the 1960s – always fails. These movements want to tear things down, divide Americans, reject and replace our national foundations.