How Death Outlives War: The Reverberating Impact of the Post-9/11 Wars on Human Health, published by the Costs of War project at Brown University's Watson Institute, focuses on what [author Stephanie Savell] terms "indirect deaths" " caused not by outright violence but by consequent, ensuing economic collapse, loss of livelihoods, food insecurity, destruction of public health services, environmental contamination and continuing trauma, including mental health problems, domestic and sexual abuse and displacement. Calculated this way, the total number of deaths that occurred as a result of post-9/11 warfare in Afghanistan, Pakistan, Iraq, Syria, Yemen, Libya and Somalia rises dramatically from an upper estimate of 937,000 to at least 4.5 million, of which up to 3.6 million were "indirect deaths". Such deaths grow in scale over time. In Afghanistan, where the war ignited by the 2001 US-led invasion ended in 2021, the indirect death toll and related health problems are still rising. Experts suggest "a reasonable, conservative average estimate for any contemporary conflict is a ratio of four indirect deaths for every one direct death", Savell says. The poorer the population, the higher the resulting indirect mortality when conflict erupts. Savell does not attempt to apportion blame between various actors, although the US, which launched the "global war on terror" in 2001, bears heavy responsibility. An estimated 38 million people have been displaced since 2001.