Emergencies, whether of war, pandemic, flood or fire, threaten our sense of security and sharpen our expectation of what governments might or should do. The experience of COVID-19 repeats at a century’s distance the even more devastating influenza epidemic of 1919. In each case, the politics of emergency response has exposed tensions in the Australian federation. The states’ primary responsibilities for health have been an insurmountable obstacle to centralising tendencies in the federal response. Long-standing constitutional foundations of the ‘police power’ of modern government point to the importance of recognising rather than regretting the strengths of the states in the Australian federation.