A bit heavy read, with some repetitions, and a mass of well quantified horrors. Fortunately, two useful annexes to restore some order: Numbers and Terms, and Abstract.
Hitler called his enemies "Marxists", and Stalin called his "fascists". They agreed that there was no middle ground.p 75
Eight high commanders of the armed forces were show-tried that same month; about half of the generals of the Red Army would be executed in the months to come. Of the 139 members of the central committee who took part in the party congress of 1934 (the Congress of Victors), some 98 were shot. All in all, the purification of the armed forces, state institutions, and the communist party led to about fifty thousand executions.
These operations were directed against national groups that, taken together, represented only 1.6 percent of the Soviet population; they yielded no fewer than thirty-six percent of the fatalities of the Great Terror.
The moral danger [...] is never that one might become a victim but that one might be a perpetrator or a bystander.