The exact same factors that preceded the collapse of Rome have taken place in America, over a similar time frame.
In the third and fourth centuries Rome debased its currency. The Denarius started out as almost pure silver, maybe as much as 90% like the American silver Dollar. Over time, especially at the hands of Diocletian, Roman currency declined over 30 years to just 5% silver. This leads to rapid inflation.
All this extra money, now worthless copper, goes to paying for the grain dole.
A significant portion, up to 40%, of the population of Rome was living below the poverty line and relied on free grain and olive oil to survive. The debasement of the currency hurt the poor even more, as did the institution of slavery. The Roman economy was built around slavery. Hero of Alexandria discovered that steam power could be used to do work 300 years before the crisis of the third century, and yet there was no industrial revolution in Rome because there was an unlimited supply of slaves that could do that work for less cost. It is impossible to compete against a slave. A slave will work for next to nothing (just the cost to feed and house them). A free worker cannot negotiate wages when the boss could just fire the worker and buy a few slaves. Since Roman workers have no leverage and no means of negotiating that means they are fully at the whim of the monied elite. You either accept the starvation wages or you don't have a job. As a result a large number of Romans, half a million within the city itself, needed to be given free food from the government just to survive.
The situation is not helped when half a million to 1 million Goths crossed the Danube into Moesia and Dacia. These people need food, they need shelter, and they need employment or they will destroy the fabric of Rome itself. A million hungry, homeless people with nothing to do is an army that poses an existential threat to the empire. Many sold into slavery while others are paid to be mercenaries in Rome's army, where they acquire valuable military training and knowledge of tactics that they will use later on when they sack Rome.
The Goths destabilise the empire, just as every large migration has done throughout history. Every time a civilisation accepts whole populations of people into their borders it is not long before that civilisation collapses. It happened with Rome, it happened in China, it happened in the New World, and every other place mass migrations have occurred.
The debased currency is also used to fund an endless war in Persia (modern day Syria and Iraq were part of the Persian Empire). The war with Persia had been going on since before anyone could remember, and it would continue until the Western Empire collapsed. Hundreds of thousands of soldiers were killed in the meat grinder, achieving nothing, and vast sums of money were thrown at the war hoping it would make a difference. In the end both Rome and Persia were spent. Their economies collapsed, their armies had been devastated, and all it took was a single gust of wind to blow the two superpowers over.
From out of the desert a new tribe of barbarians appeared that no one had ever seen before. Their leader claimed to speak directly to God and his bands of terrorists were able to conquer Persia, Egypt, and north Africa within a generation. Syria fell but was recaptured by Rome after a desperate counterattack using an unknown weapon that burnt the Arab fleet to dust.
In the West the Goths sacked Rome. Hispania and Gaul fell to the barbarians. Byzantium managed to hold onto Italy for a little longer, but it too would fall after a few more emperors came and went.
The exact same thing is happening in the United States.
Starting in 1913 the US Dollar has been devalued thanks to the Federal Reserve that can print an unlimited amount backed by no hard assets. In the past century the Dollar has lost more than 95% of its value. In my own lifetime the Dollar has lost over half of its value.
At the same time wages have stagnated for the past almost 40 years. People talk about a $15 minimum wage and how it will destroy the economy. If the Dollar had lost none of its value since the 1970s minimum wage would be over $21 an hour! Sure, you would technically get something like $1.50, but it would be the equivalent of $21 in 2017 Dollars. It really was possible to live off of minimum wage 40 years ago, and today we're told that no one was ever supposed to, all the while millions of people are forced to because there are no other jobs available.
There is also an analogue to slavery in America. Corporations are able to abuse the H1B visa to import tens of thousands of workers from countries like India who can be paid the same wages of their home countries. An Indian tech worker needs only be paid $20 an hour for the same job that an American worker would need to be paid $80 an hour. It is cheaper to hire four foreign workers on visas than it is to hire one American, so Americans lose their jobs. And that's just at the top end.
Millions of people have migrated to America illegally. The official number is 11 million, but the reality is closer to 40 million. Those people can be hired, illegally, and paid pennies on the dollar for American workers. And because if they complain they will get deported they are willing to work in horrible conditions that would otherwise be illegal under US law. This is not slavery under the Roman model, in a sense it's worse. Roman slaves were guaranteed food and housing, illegal immigrants are guaranteed neither. And just like the giant conglomeration of Goths who were employed as slaves in Rome, the various peoples in the US illegally speak their own language, have their own culture and customs, refuse to assimilate, are directly taking tens of millions of jobs from US workers, and are depressing the wages of all other US workers. They also bring in diseases that had long been eradicated in the US, like tuberculosis and measles, just as the waves of barbarian migrations brought plague to Rome.
And the war in the Middle East that had refused to end in Roman times has still yet to end, and the US is ensnared in that war just as surely as Rome had been. Iraq and Syria, and Afghanistan (which was also part of the Persian Empire) are bleeding American manpower and treasure for absolutely nothing. $2 trillion spent on pointless wars in the past 16 years, combined with inflation and devaluation of the currency, it's a recipe for disaster.
Rome had been critically weakened by deficit spending, pointless wars, mass migration, and slavery depressing wages. All it took was a single army of nomads to blow over the Roman Empire.
The same is happening in America, and in Europe. The same factors of deficit spending, pointless wars, mass migration, and depressed wages have destroyed the American economy, and in Europe we have seen 2 million Muslim "refugees", mostly young men in their 20s to 40s, have stormed the gates of the continent and have begun sacking cities such as Paris, London, and Berlin. It's already too late to save Europe from the Islamic invasion. They have already fallen just as Rome had a thousand years earlier.
There is still time to save America. We can still leave the Middle East to its own devices, we can still cut the flow of illegal migrants across the border, we can stop spending money that does not exist, and we can restore the economy by creating American jobs for American workers. We can reverse the damage that had burnt Rome to the ground and is setting alight the cities of Europe. We can keep the Islamic armies from invading and dealing the death blow to the weakened empire.
But we need to act fast. The collapse of Rome happened in stages. The West fell during between the fourth and fifth centuries, and it was not until the seventh century that the invasion of Islam destroyed much of the East. Today we do not have the luxury of time. We cannot wait 200 years for Islam to rise up and destroy the West, weakened by its decadence, it is already hear invading Europe. Every week there is another terror attack and we are told to shut our eyes and cover our ears and to put out from our minds the thought that it is Islam that unites all these attacks.
We always have to say, to cover our asses, that there are good Muslims, and there are. The problem is the US government doesn't like good Muslims. The US government likes to kill the good, secular Muslims like Saddam Hussein and Muammar Gaddafi, and the US has set its sights on Bashar al-Assad. We are told, by the controlled media, that these men are vicious killers and they should be eliminated. While it is true that they are strongmen who are merciless in dealing with their enemies, those enemies are the same terrorists who are flooding into Europe now. The enemies of strongmen like Assad are the same enemies of the West, and the enemies of the average person in the Middle East as well! And, truth be told, the United States is no stranger to mass murder, whether it be dumping Agent Orange on Vietnam, or depleted uranium in Iraq, or firebombing the civilian population of Dresden. Serbia, Grenada, Nicaragua, throw a dart at a map of the world and try to find a place the US has not bombed or invaded. The US calling Assad a monster is another case of the pot calling the kettle black.
The United States is flawed, but,just like Rome, it represents the light of the world. Both were built on the Hellenistic foundation created by Alexander the Great, a foundation that says that one's origin does not matter, anyone can rise to great heights by adopting the Hellenistic culture. Because Hellenism is meritocratic. It is humanistic, and it is just. The world was impoverished by the fall of Rome, and it will be impoverished to an even greater extent by the fall of the United States. That is why it is imperative that we preserve the light of Western Civilisation through the means I have outlined above: ending the war, ending deficit spending, cutting off the flow of illegals over the border, and preserving Western culture against the onslaught of seventh century Islam and post-modern degradation. There's still a chance to save the flame of liberty, reason, and justice, but that flame is dangerously close to going out, and once it's gone it might never be rekindled again.