Red-tagging in the Philippines is a way for the government to identify people and organizations as threats to national security. The government does this by labeling them as communists or terrorists. This means that if you are red-tagged, the government thinks you are a dangerous person who wants to hurt the country. People who are red-tagged can then be treated differently by the government, and be arrested or even killed. The government also uses red-tagging to silence people they don't agree with or want to stop them from speaking out.