As they argue, there is a general incentive problem with relying entirely on private sector vaccine capacity. Before the pandemic, vaccines were a relatively modest part of the pharmaceutical sector, largely because most of them are only taken once or twice — just 3.5 billion doses were produced per year of all vaccines combined. That problem was made worse by the just-in-time production model that has become standard across all business over the years, which meant companies have kept spare capacity as low as possible. Now that we need on the order of 15 billion doses as soon as possible, private companies are scrambling to meet the need. (Indeed, one reason Canada has been struggling with vaccination is that its government privatized its state-owned vaccine factory in the 1970s.) There is every reason for the U.S. government to simply build and own a permanent, large vaccine factory — both for jacking up production immediately, and to keep on hand for the future. In the context of the staggering damage the pandemic has inflicted on the global economy, the cost would be microscopic, only about $4 billion. As Krellenstein and Urrutia explain, the Moderna vaccine is the best candidate for mass production, because it is easier to scale up, more temperature-stable, easier to adapt to variants, and the American government already owns some of the intellectual property rights. (Moderna could also be hired to operate the facility.) As they write, "For less than the U.S. government spends on the COVID-19 response daily, it can build a facility to produce enough mRNA vaccine manufacturing capacity to vaccinate the entire world in one year, with each dose costing only $2."