There's enough horror in American history, and depictions of them, to keep these committees busy for a long time. Washington, Jefferson, the confederacy, westward expansion, and slavery were not very controversial historical topics just 60 years ago.
Think about all of the events/figures likely to offend at least one vocal group maybe not now, but in the future:
- Andrew Jackson (purveyor of genocide)
- Theorore Roosevelt (bloodthirsty militarist)
- WWI (unjust war)
- Transcontinental railroad (genocide's superhighway)
- Texas war of independence (slavery)
- Moon landing (cold war publicity stunt)
- The Manhattan Project (America's WMD program)
- Albert Einstein and FDR (for kickstarting the world's nuclear nightmare)
- Lyndon Johnson (genocidal maniac)
- George W Bush (bloodthirsty militarist and torturer)
- Barack Obama (architect of America's robotic warfare system)
- Donald Trump (basically everything he ever did)
- The Republican Party (for supporting Donald Trump)
Some of these events/figures seem like a stretch. Maybe they are, but a lot can change in 60 years. The point is that we now have ample evidence for very vocal groups calling for, and getting action on, suppression of vast swaths of American history in the form of artwork and symbols.