Modern historians and media have always portrayed Ancient Romans and Roman emperors as being cruel and savage people. However, compared to modern 20th century governments, we can see that this picture of the Romans is a distorted one. The Ancient Roman culture did not produce ruling monsters the size of Stalin, Mao Tse-tung, Hitler, and Islamic fundamentalists who caused the death of millions upon millions of their own people as well as minorities in the name of an ideology and a religion. They also did not have presidents like Harry Truman and Lyndon B Johnson, who ordered the firebombing of Tokyo, Osaka, Bremen and Vietnamese cities, respectively, and the nuclear bombing of Hiroshima and Nagasaki, killing millions of women and children just because they wanted to increase their popularity by putting World War II and the Vietnam War to an end, taking the soldiers out of the battlefield and be elected presidents on their own (they had succeeded incumbent presidents). They also did not have Islamic terrorists, whose only objective is mass-murder of civilian population because the fundamentals of their religion say so.
I know you are going to say that Emperor like Caligula or Nero would have used atomic weapons if they had that technology, but these monsters were killed by the Praetorian Guards when things started to get out of hands, which paved the way for emperors such as Trajan, Adrian, Antoninus Pius and Marcus Aurelius.
We must not get actual human events out of its historical and cultural context, for the Romans and the Greeks were the products of their time and had completely different cultural mores (the values that constitute the cultural fabric of a given civilization) than human beings of today. And one of their moral values was “courage”, and, in order to get social acceptance, a military had to fight face to face with the enemy on a given battlefield, and the enemy had the form of an armed soldier, not women and children. We must judge the Romans in their historical circumstances; in ancient times, an ordinary Roman citizen enjoyed the highest standard of living and political and social freedom in antiquity; Rome was also the only City-State to grant citizenship to foreigners. The Romans were vicious only with those nations that tried to destroy Rome, like Carthage.
In Ancient Times, specially among the Romans, the cultural values revolved around survival of the individual and of the group (clan, tribe, nation), never around monotheistic religious doctrines or political ideologies. The Romans would never waste their money, time and energy building pyramids to honor a tyrant, for example, for it was useless for survival; they would rather build bridges, aqueducts, irrigation systems, and a strata via (roads), because these were useful for the Roman citizens, who were living human beings. The Soviet Union, Communist China, and Cuba squandered away precious government income to deify and worship their tyrants, like Mao and Stalin; the result, terrible famines that wiped out entire populations.
In time of war, the objective of the Roman consuls and emperors were the conquest of a hostile nation to ensure the survival of Rome, which was completed through a process called romanization of that region.