Well, we’re not a “Christian nation” actually. While we may be a nation that has some Christians in it, it’s not a “Christian nation”.
This nation can’t be a Christian nation and at the same time support, legally, the killing of 43 million babies in the last several decades. The two don’t go together.
But, it can be a nation where there is a minority of Christians who still live here.
AND, yes..., in the past, when the nation was founded, it could be called a Christian nation in terms of what the nation did “corporately speaking”. Not now, though....
It is true that many practice “Situational Morality”.
Still, all of have fallen short of the Glory of God and that is why we become Christians. God doesn't waive a magic wand and give us the ability and consciousness of righteousness and to always act accordingly.
He does give us free will and a conscience and that all actions have a consequence.
In other words we don't suddenly become perfect. If we were, why would we be stuck on this rock?
God gives us a salvation of our own volition. Whether we choose to act as Saul or convert ourselves into Paul is up to us.
Doesn’t make one less of a Christian but less of a person.