Rome fell due to rot from within. Jesus' birth was not a contributing factor. Indeed, one can argue that the Roman Empire was prolonged by Christianity after it was co-opted by Emperor Constantine and the Council of Nicea in the year 323.
Are we supposed to look at Roman power as a lost greatness to be regained?
We can look to the root causes of the failure of great empires to check for weaknesses in America's status as a superpower today. The same corruption that destroyed Rome is growing within our three branches of government. Whether it can be fixed is the question. Another Clinton presidency, I fear, would be fatal.
And I would say that the willingness to accept the torture of our fellow human beings is symptomatic of a different kind of corruption, a corruption that can also destroy us from within. Ask yourself: is there any version of torture, of a human being subjected to unimaginable pain for the furtherance of another human being's ends, which you think Jesus would look down at and say "yes, this is what God has in mind for His children"?