A state of emergency is a government declaration that allows it to put through policies it would normally not be allowed to for the safety and protection of its citizens. It is usually triggered before, during, or after a natural disaster, civil unrest, armed conflict, medical pandemic, or other biosecurity risk but may also be caused by political protests, economic crisis, or even a severe weather event (such as an extreme heatwave). It empowers the government to do things it normally could not do and extends its power over the whole country or a specific region.
Each country has its own laws on how to declare a state of emergency. The constitutions of some countries allow it only in cases of danger to the constitutional authorities or the state as a whole. Others, like the Argentine Constitution, allow states of emergency (literally estado de siege) to be declared when internal unrest or foreign aggression threatens the nation. This was often abused during dictatorships, with long-lasting states of emergency allowing the regime to suppress any opposition.
In the United States, the President can declare a national emergency or a state of emergency if the nation faces a serious threat to its security, health, or welfare. During a state of emergency, federal aid is available and the President can authorize the use of military forces. In Macau, the Standing Committee of the National People’s Congress can declare a state of emergency and deploy troops from the People’s Liberation Army Macau Garrison under Article 14 of the Basic Law on the defence of the Special Administrative Region.