In July, a local news arm of CBS reported a "disturbing and potentially dangerous trend in one New Jersey community". Days before the Independence Day celebrations, someone had set fire to several of the US flags hanging outside the homes of Roselle Park residents. "It was just shocking to me," one victim, Jill Stanton, said. "There was nothing left . . . It was burned down to the metal."

Predictably, the comment thread below the article soon teemed with disproportionate expressions of disgust, many of which deviated from the story to blame immigrants, Marxists, Islam, Obama (or "Obozo", as the retired John calls him) and liberals for the ills afflicting the home of the brave, if not the world.

Those who disagreed with the onslaught of paranoia and xenophobia were met aggressively: "Could you be a Muslim? Wife wear a burqa? Daughters afraid to cross you lest you cut her head off? Who was it that flew those planes into the WTC?" wrote Julia. J-man, meanwhile, suggested what can only be described as a final solution: "Were I the president of the US in 2001, I would have flattened [the] precious Muslim world with saturation nuclear strikes."

This extreme or, rather, extremist veneration of the national flag may seem absurd; yet the culture behind it has roots going back to the immediate aftermath of the American civil war. In a bid to protect that symbol of fragile national unity from southerners who preferred the Conferederate alternative, 48 states declared flag desecration a criminal act.

More recently, in 1968, Congress passed legislation that made it illegal to "knowingly cast contempt upon any flag of the United States by publicly mutilating, defacing, defiling, burning or trampling upon it". This was overturned in 1989, when the Supreme Court ruled that such acts were constitutionally protected as forms of free expression. Justice William Brennan, who presided over the case, eloquently summarised his reasoning as follows:

We can imagine no more appropriate response to burning a flag than waving one's own; no better way to counter a flag burner's message than by saluting the flag that burns; no surer means of preserving the dignity even of the flag that burned than by . . . according its remains a respectful burial. We do not consecrate the flag by punishing its desecration, for, in doing so, we dilute the freedom that this cherished emblem represents.

In the UK, where it was illegal to suspend the Union Jack without permission from the local council until 2006 (unless it was from a vertical flagpole), national flags seem to bear less of an ideological burden. Yet the recent controversy over the Islamist group Muslims Against Crusades, which burned Remembrance Day poppies last November in protest against western foreign policy, shows that the corrosive impulse to stamp out opposition is alive and well this side of the Atlantic.

Elsewhere on Newstatesman.com, Nelson Jones and Steven Baxter have written in depth about the self-defeating nature of Theresa May's decision to proscribe the organisation -- and I wrote about the banning of Islam4UK, its previous incarnation, for Pickled Politics in 2010 -- so I won't repeat the argument here. Instead, I'll cite the words of Robert Jackson, a US judge who, in 1943, struck down a law requiring schoolchildren to salute the stars and stripes:

Freedom to differ is not limited to things that do not matter much. That would be a mere shadow of freedom. The test of its substance is the right to differ as to things that touch the heart of the existing order. If there is any fixed star in our constitutional constellation, it is that no official, high or petty, can prescribe what shall be orthodox in politics, nationalism, religion, or other matters of opinion or force citizens to confess by word or act their faith therein.

Fallen soldiers deserve respect, regardless of the moral ambiguities of the campaigns in which they served. The appropriate response to the attention-seeking idiocy of Muslims Against Crusades is, as Justice Brennan might have said, to counter that group's flames with a salute.