We aren't more peaceful now. We're just better @ hiding the dead bodies.
Yeah... we're better at hiding the bodies now in an age of perpetual satelite surveillence, networked communications which mean a cow can't sneeze in Chad without Moscow knowing about it, greater public travel, greater public awareness of... oh what's the use? You've already made up your mind, haven't you?
Fewer people are involved in violence now
Roman population ~65million (of whom 2-10million were slaves)
Roman army ~0.5million
Percentage of populace in army = 0.8%
American population ~320 million
American armed forces ~ 1.4 million
% of pop. in army = 0.4%
Of course, Rome isn't typical and neither is the US. States like Sparta had virtually all males enlisted and would regularly go to war with the other Greek city states. The only reason we appear to be more violent now is that the weapons are more... dramatic. A single nutter with a bomb can kill thousands if placed right. The most anyone could expect to kill with a spear or sword is a few hundred.
This isn't a problem just with Yaakov, regularly the crime statistics show that crime, especially violent crime is falling, and yet the fear of crime continues to rise.