I think you're arguing a strawman version of my point. I'm not claiming that it's impossible for them to know something we don't. I'm just saying that the assumption that there is secret information that makes his actions sensible is not well founded.
There are numerous examples of leaders claiming expertise that wasn't borne out. And if this were the case, I think it would be reasonable to expect them to at least claim this to be the case.
As it stands, this behavior can be fully explained with the information available to us and Biden's foreign policy stance. So there is no reason when you see him doing something that can be easily explained by the observation that he has poor judgement and priorities that are wildly different than most Americans to believe that there is a reason outside of the public facts and our existing knowledge of his poor judgement and unpopular priorities.
If it makes you feel any better, I remind myself that I myself am subject to the same irrationalities and motivated reasoning as anyone else. We're all just people, and people aren't logic machines. We're bundles of impulses and habits that live within whatever stories our minds have to create to make sense of all of this.
In this context, if you're looking for some kind of remedy, the best I can offer is that instead of trying to bother disputing with myths and superstitions, recognize that anyone who grows out of them usually does so because they find some other way to the same fundamental bedrock notions. Your friend wants to adhere to the rules laid out by the creator. They want to be worthy of Christ's love.
I think if you were inclined to change their mind -- which I'm not recommending -- it would be when this comes up to remind him how many people have been seduced into supporting ungodly things thinking they were following God's will. That's Satan's number one tactic. So all we can do is stay humble and listen to our hearts. If seeing kids living in Bethlehem struggling to survive under an oppressive king just as Jesus and his parents did seems wrong, it's okay to not have a confident stance. Maybe your pastor says it's God's plan, but no one -- not even the disciples -- could ever no God's plan for sure. You don't have to have a stance. You can say "God's will will be done. He does not require my involvement."