If anything epitomises the fall of a once great civilisation then the Parthenon in Athens is a classic example. It is a visible symbol of the decay that can befall any civilisation when it takes for granted the benefits of its success and ceases to nurture the things that made it exceptional.
External enemies are the obvious threat but more insidious and corrosive are the enemies within, slowly but incessantly chipping away at the institutions and culture that evolved over two millenia and surreptitiously undermining the very foundations of the country to which they claim allegiance.
The slow, deliberate degradation of western civilisations by internal enemies acting on behalf of the UN/EU ruling elite has suddenly changed from the generational process it has employed up until now into a scorched earth type dash to destruction as the people wake up to their plan and rebel by rejecting the establishment politicians and switching their allegiance to more popular movements.
It's worth noting that all the countries that are being 'fundamentally transformed' against the wishes of the majority and disfigured beyond recognition are not third world dictatorships or oligarchies but prosperous, free and open multi-party democracies, with supposedly independent judiciaries along with guaranteed freedom of speech.