I am giving these examples because I am concerned about how our future generations yours and mine will cope with the growing pressures on our religious heritage not least from the sharp increase in the Muslim community
You make a lot of assumptions in your post. I would like to point out that most of the arguments critics of Christianity use to justify themselves without a savior are refuted on numerous websites:
However, it is important to understand what God says about unbelief. Since he is all-knowing, it eliminates a lot of frustration in determining what is going on.
Unlike the animals; man alone is unique with his innate notions of morality and the awareness of God. Someone once said that with great gifts comes great responsibility. This is especially true in the area of moral justice and the innate knowledge of God.
And yes, we are innately aware of God’s existence and his moral justice, from infancy.
Romans 1: 18 & 19 states: For the wrath of God is revealed from heaven against all ungodliness and unrighteousness of men, who hold [holds down] the truth in unrighteousness; because that which may be known of God is manifest [shining] in them; for God hath shewed it unto them. - KJV
God says here that the knowledge of him is already shining within us, even as sinners, but that the real problem is that unrighteous people suppress or push down this truth within themselves. People tend to imagine God as they would like him to be, or as they have been misled into believing him to be, rather than as he actually is as revealed in our hearts and his word the bible.
This is really bad news for humans who entertain various illusions about God because God maintains that they are still accountable. It is this accountability that the gospel message of justification addresses. It is not our culture that is at stake here but our souls:
Hebrews 9:7 it is appointed unto man once to die and then judgment
You will find that the knowledge of God is equally suppressed among all those that are damned. It is a psychological trick the mind uses to justify itself apart from God.