Today there are more practising Muslims than practising Christians in most countries of Western Europe.
The secular Europeans may see the danger of Islamization, but only from the standpoint of crime and employment. They neglect the looming specter of what the Koran and Sharia Law have in store for their future. They ignore the reality they will soon become second class citizens in their own countries, and they won't even realise "why".
The enemy is not only at their doorsteps but in their living rooms. They think this is "company" whom they can invite in and coexist with - with Western European Christendom remaining the dominant culture. But to them Christ is dead or non-existant and only the surface remnants of their rich culture and mores survive. There is no "there" there. They will shortly find out how wrongheaded they are in these assumptions. The tipping point will come when Muslims start demanding, and getting, Sharia Law - first in their own communities and then spreading it into entire legal systems.
They're developing an addiction to Islam. First they're fed a little taste which they find harmless. Then a little more and a little more until they find that there's nothing they can do and they HAVE to have it.
Yup. The first warning sign is when the first hamlet or town implements sharia. Then you'll know that Europe is in its death throes.
Godspeed