A Clean Break is a new strategy for keeping a country safe. It means that a country would take steps to protect itself by making sure it doesn't have ties or connections to other countries that could be unsafe. This could mean things like making sure a country isn't trading with other countries, keeping military forces and resources separate from other countries, or having diplomatic talks only with countries that are safe and friendly. It's a way for a country to look out for its own interests and protect itself from harm.