The National Anthem as Idolatry

I am very bothered by the high school custom of standing before a sports event starts, putting your hand on your chest respectfully, turning to face the flag, and singing a song in its praise. This sure seems like outright idolatry, the kind that the Bible condemns so strongly. On the other hand, so many Christians do it and have done it for so long with so little comment that I have to wonder if I'm seeing it wrong somehow. I'll look for references on this, but googling turns up nothing useful. There are a lot of people who don't like America much and object to the National Anthem, and patriotism generally, on that basis. I have no objection at all to patriotism and love of country. People can talk about metaphorical idolatry with respect to anything whatsoever-- lust, food, new cars, Beethoven, great art, videogames, etc.--- because literally anything can replace God as a person's source of value and loyalty. No-- what I'm worried about is LITERAL IDOLATRY: worshipping images. That's, on it's face, is what we do when turn to the flag, try to feel respectful, and sing a song in its praise. Is there a way to overcome this prima facie case that apparent worship of a flag is actual worship?

Here are various relevant verses: 

Thou shalt not make unto thee any graven image, or any likeness of any thing that is in heaven above, or that is in the earth beneath, or that is in the water under the earth: Thou shalt not bow down thyself to them, nor serve them: for I the LORD thy God am a jealous God, visiting the iniquity of the fathers upon the children unto the third and fourth [generation] of them that hate me. (Exodus 20:4-5)

Ye shall make you no idols nor graven image, neither rear you up a standing image, neither shall ye set up any image of stone in your land, to bow down unto it: for I am the LORD your God. (Lev 26:1)

For thou shalt worship no other god: for the LORD, whose name is Jealous, is a jealous God: Lest thou make a covenant with the inhabitants of the land, and they go a whoring after their gods, and do sacrifice unto their gods, and one call thee, and thou eat of his sacrifice. (Exo 34:14-15)

Now the works of the flesh are manifest, which are these; Adultery, fornication, uncleanness, lasciviousness, Idolatry, witchcraft, hatred, variance, emulations, wrath, strife, seditions, heresies, Envyings, murders, drunkenness, revellings, and such like: of the which I tell you before, as I have also told you in time past, that they which do such things shall not inherit the kingdom of God. (Galatians 5: 19-21)

There hath no temptation taken you but such as is common to man: but God is faithful, who will not suffer you to be tempted above that ye are able; but will with the temptation also make a way to escape, that ye may be able to bear it. Wherefore, my dearly beloved, flee from idolatry. (I Corinthians 10:13-14)

Little children, keep yourselves from idols. (1 John 5:21)

Also relevant is the "weaker brethren" passage:

Howbeit there is not in every man that knowledge: for some with conscience of the idol unto this hour eat it as a thing offered unto an idol; and their conscience being weak is defiled. But meat commendeth us not to God: for neither, if we eat, are we the better; neither, if we eat not, are we the worse.bBut take heed lest by any means this liberty of yours become a stumblingblock to them that are weak.For if any man see thee which hast knowledge sit at meat in the idol's temple, shall not the conscience of him which is weak be emboldened to eat those things which are offered to idols; And through thy knowledge shall the weak brother perish, for whom Christ died?But when ye sin so against the brethren, and wound their weak conscience, ye sin against Christ.Wherefore, if meat make my brother to offend, I will eat no flesh while the world standeth, lest I make my brother to offend. (1 Co 8:7-13)

A big issue is what it means to worship an idol. The flag is certainly an idol, a physical representation of the United States. The United States is not exactly a god, though. It is not a supernatural person, or a natural one. We do not makes prayers of petition to it, though we do make prayers of adoration and I expect some people make prayer of thanksgiving. 

The Chinese Rites Controversy may be helpful.

The debate discussed whether Chinese ritual practices of honoring family ancestors and other formal Confucian and Chinese imperial rites qualified as religious rites and were thus incompatible with Catholic belief.[1][2] The Jesuits argued that these Chinese rites were secular rituals that were compatible with Christianity, within certain limits, and should thus be tolerated. The Dominicans and Franciscans, however, disagreed and reported the issue to Rome.

Rome's Sacred Congregation for the Propagation of the Faith sided with the Dominicans in 1645 by condemning the Chinese rites based on their brief. However, the same congregation sided with the Jesuits in 1656, thereby lifting the ban. ...Clement XI banned the rites in 1704. ... In 1939, after two centuries, the Holy See re-assessed the issue. Pius XII issued a decree on 8 December 1939, authorizing Chinese Catholics to observe the ancestral rites and participate in Confucius-honoring ceremonies.

The decree Cum Deus Optimus of 20 November 1704 banned the rites. The 19 March 1715 Papal bull Ex Illa Die confirmed that, and in 1742 Ex Quo Singulari. A decree (not bull) of 1939, Plane Compertum, said that

Catholics are permitted to be present at ceremonies in honor of Confucius in Confucian temples or in schools; Catholic magistrates and students are permitted to passively attend public ceremonies which have the appearance of superstition. It is licit and unobjectionable for head inclinations and other manifestations of civil observance before the deceased or their images.