Catherine of Siena has a particularly relevant story as our world faces what could be the Black Death of MMXX. One hundred seventy years before the Protestant Reformation, the plague of the day swept through Siena, and by AD 1349, half the population was dead. Half. Fifty percent. Not one percent. Not two percent. Fifty. In some places even sixty percent. They didn’t have tests. So maybe somebody exaggerated. So let’s just round down to fifty.   In the middle of this—the first of several such pandemics—Catherine was born. Her parents’ twenty-fourth child, Catherine lost a twin at birth. A younger sister after her died as well, making Catherine the youngest of a…