The fundamental issue at play here is that Protestants in general reject all earthly authority except the authority of self - proxied through the bible. By proxied I mean they attempt a faux modesty by ostensibly deferring to the “authority of scripture alone” (sola scriptura). But this is just a means to put the Holy Spirit to the test so to speak and essentially cast lots to interpret scripture in any way that makes sense to them personally. Clearly this is not an objective standard and is prone to human weakness and bias and is subject to deficiencies in personal moral and intellectual facilities.
This is a very difficult thing to get Protestants to see since they are in a hubristic comfort zone that they are simply blind to. This is the very nature of hubris. So through a self inflicted delusion that they rely on scripture to self-interpret they may freely ignore the natural conscience and the bliss of faux certitude in scripture still pragmatically leave themselves “in control” through private interpretation. This error replaces the pope in a way that let’s each sola-scripturist be their own private pope and in so doing each eventually loses the benefit of external checks and balances against personal bias.
As a point of illustration consider bookkeepers and accountants. Frankly I can’t imagine how any bookkeeper or accountant could ever be a protestant since these objectively know through training that the principal of self-auditing is unreliable and objectively impossible. We need checks and balancing as well as external auditing.
So, what needs to be overcome is the inherent seductive power of self-interpretation of scripture that permits anyone to interpret scripture to suit and promote any-one’s personal whim or proclivity from orthodox principals. This personal empowerment (which is really enslavement to personal bias), except for the secular benefit of social networking and support, renders “the church” irrelevant to salvation. This is the core error that we face and it is figuratively seen as individual sheep leaving the safety of the flock. It’s not just a matter of going out and finding the scattered sheep - its also a matter of convincing them to stay and not run off again once we get them back.
Thus a Protestant secure in his own apparent empowerment sees no compelling reason to adapt the Catholic conviction that “the church” as a necessary and integral part of God’s salvation plan. They simply and mistakenly think they have everything they need for salvation in their own personal “church of one”. So Protestants under the domination and seduction of “self-determination” and “self-sufficiency” find it nearly impossible to escape a self-centered individualized and personalized perspective of salvation.
So I agree with the prior poster who sees rejection of ecclesial authority as an important factor. To accept the Catholic alternative the Protestant has to radically reconfigure her thinking and: 1) accept that The Church is not only valuable but in fact integral to salvation and 2) accept that there is such a thing as valid divine given ecclesial authority while being convinced of the extreme bias inherent in self-policing private interpretation.
At a spiritual level the spiritual demon at work here is the top demon - Lucifer, the demon of Pride. Catholics know through our teaching authority that the antidote to demonic pride is humility. Catholics get aquainted with humility in sacramental confession - but Protestants do not belive in this. So we need to find a way to get Protestants to recognize the self-limitations of individualism and get them to bend their knee to legitimate authority and deffer personal will to a collective greater good. This is a very hard task and usually requires that one fall victim to the consequences of “self” and come to realize one can’t reliably “do it” alone.
The first step then is to replace pride with humility. This is a very tough voluntary sell in this secular post-enlightenment era that values reason and individualistic self-expression over moralistic and all other considerations. My own opinion is that reason competing in the context of self-interest will never prevail to discover the deficiency in self determination and self sufficiency. I pray for reason to prevail of course. But I am afraid that it will take a divine act of God to wake up the planet so reason can prevail and let everyone see that we are all “in the womb of creation together”.
If there is a human solution it is to provoke reason on a grand scale to increase anxieties to get everyone to wake up and come to their senses. But this is revolutionary in nature and very dangerous. So this is really God’s domain, not man’s domain. Therefor prayer is really our only best single first step.
The larger problem is that I think the fundamental Islamics are way ahead of us. They are hard at work on their own private ideas about just how best to provoke the planet to come to their deficient and disordered interpretation of how best to submit to God. So, we Christians are facing a count-down and are compelled by urgency to come together in prayer before an incompetent and unmerciful human solution is attempted.
Bottom Line: Prayer.