I don't agree, for two reasons: (1) it is only a personal opinion that flying some banner that you and some other people call Christian above or below the national flag--if the church even chooses to fly the nation's flag--represents what you think that placement of flags does, and (2) it's not the flag of Christianity, the Christian "nation," or anything else like that. Someone just invented that design and a few churches use it and mean by it whatever they choose to think. I doubt that very many of them think it's in competition with the nation's flag as some sort of flag of what you call a "Christian nation."
I understand what your opinion is. It's incorrect IMHO and I explained why that's so.
It saddens me that you have gone so far as to declare my concern as "incorrect"--simply judged so by your opinion without any listed Scriptural backing. It is one thing to have differing opinions (disagree), it is a whole other thing to declare something "incorrect" based on the weight of one person's opinion or another's. Shouldn't there be more Scriptural support, if you are going to make that determination?
(1) Your logic is incorrect--not based on my opinion--but based on what is said in regulations concerning the US flag. Value is given to the US flag, which is just a piece of cloth in and of itself. As a result, there is a whole code of expectations about how it should be displayed, when displayed. Here is one website displaying the Flag Code:
Flag Code | The American Legion
(2) According to the Flag Code (not my opinion): if a flag's position is lower or leftward, it is considered of lower prominence (as noted on the website above). And, that is an expectation for all flags on US soil, that are displayed with the US Flag--with few exceptions, according to the Flag Code. Apparently, other nations also require their flag to be flown above all other flags on their soil, as well. So, this is not only a US custom. It is internationally recognized.
(3) Therefore, it is not absurd, or incorrect, to assume that someone flying or using another flag doesn't subscribe some value to it. If they didn't, they wouldn't fly it at all. I don't fly a flag that professes to be "the Christian flag" outside my house, because I don't accept that as representing God, Jesus Christ, or "the holy nation". But, if one flies it, they are subscribing some value to it. This idea is further supported by the fact that the school I spoke about had the kids pledge allegiance to that "Christian flag". Obviously (not my opinion), their rituals have placed value on that flag--as representing Christian beliefs--otherwise they wouldn't have people pledge allegiance to it.
For a Christian, should Jesus Christ ever have a position of lower prominence, as compared to anything in our lives?
I would cite that Jesus said: "Anyone who loves their father or their mother more than me is not worthy of me and he that loves son or daughter more than me is not worthy of me." (Matt 10:37) In Hebrews: "...and confessed that they were strangers and pilgrims on the earth, for they that say such things declare plainly that they seek a country. And truly, if they had been mindful of that country from whence they came out, they might have had opportunity to have returned. But now they desire a better country, that is, an heavenly; wherefore God is not ashamed to be called their God, for He has prepared for them a city." (Heb 11:13-16) Jesus says "no one can serve two masters for he will hate the one and love the other or else he will hold to the one and despise the other. You cannot serve God and mammon." (Matt 6:24) Why wouldn't Shadrach, Meshach, and Abednego bow to/worship the golden statue? (Daniel 3) Bowing is an open show of submission. If we are making an oath and declaring allegiance to a particular flag and what it represents, aren't we doing exactly what they refused to?
So considering what Jesus said about loving those in your own biological family more than Him; what if you demonstrate your patriotism to a particular country or political party more than your patriotism to God's country?