FQ, You will back me up here.
The thing that finally put the final screws to the Western Roman Empire (The "Fall of Rome", Rome was done but "The Empire" lived on as The Byzantine Empire )
Was the uncontrolled immigration of Hunnish and Germanic tribes.
Instead of raising the Barbarian's up, they were pulled down to that level.
Why would we expect a different result this time around ?
You're asking FQ for backup on history? WTF? ? ? ?

Comparisons between the US and Rome are fraught with problems. Rome
was a multi-cultural empire, made no bones about it. As long as you weren't seditious and sent your tithe to Rome on schedule, you could do what you wanted, say what you wanted, worship any cow, oryx, or stone effigy you wanted to - hell, if it was interesting enough, the Romans would probably join you in slaughtering some poor vertebrate in honoring said "deity".
The barbarians were invited into the army mostly, as auxiliaries, and later as Senators under Caligula. It was only 200 years after Julius Caesar when Rome had its first non-Roman as Emperor.
Hmm . . . about the same amount of time for us to have our first non-American as President.

Ask the Romanized Brits what a good idea it was to bring in the Saxons. Hell, ask the average Native American how popular Squanto is.
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FQ13
Uh, FQ? No one "brought" the Saxons into Romanized Britain. They kinda wandered in - swords in hand - all on their own. Same as the Pilgrims - sans swords of course.
Of course, for us to allow these un-assimilated people who do not give a flying f..k about us or our culture, whose goal is specifically to take over and dominate us and force us (contrary to our laws and very foundation) into a semblance of slavery, is a major mistake. Call it a religion, call it a movement, call it a cult - whatever, it must be stomped out and eliminated from our midst.
The "average" American is so dumbed down at this point that they will believe whatever the MSM tells them, and that is that it is racist and un-American to be against the mooslims.