Confederate general Robert E. Lee has been a clear target of protesters who want to take down monuments linked to America’s history of white supremacy. Christopher Columbus has a more ambiguous legacy. How do we assess the contributions of — and memorials to — people who did great things, but terrible ones, too? Is there a difference between famous men guilty of injustice and those whose fame was inseparable from it?

Here are some of the men and monuments that have come up for debate. In some cases it's entire careers being reconsidered, while in others it's the specific statue, or its location, that has drawn criticism. It's not easy to draw the line between what should remain and what should come down, but help us out.