The actress wasn't making a statement, however. She was sharing a photo from her latest South Africa outing – a trip to Robben Island, off the west coast of Cape Town.
Katie stood in front of a sign bearing the words: "Freedom cannot be manacled", and which featured the image of Nelson Mandela, who was imprisoned on the island for 18 of the 27 years he served behind bars before the fall of apartheid.
She captioned the picture: "My sincere gratitude to Ahmed Kathrada for showing me Robben Island today. It was an honor for me. Thank you."
She was shown around the South African Heritage Site by former prisoner Ahmed Kathrada, who – like Mr Mandela – spent 18 years in captivity there.
Katie is touring the country while she's there to film The Giver with Alexander Skarsgard and Taylor Swift.
On Monday she posted a picture with her younger co-star Odeya Rush and retweeted her message: "Night off from filming... eating sushi and playing Jenga with @KatieHolmes212." The former Mrs Cruise responded with "LoveOdeya."