Question: is it illegal to write on an american flag

Answer: No, The flag of the United States is sometimes burned in protest of the policies of the American government, both within the country and abroad. The United States Supreme Court in Texas v. Johnson, 491 U.S. 397 (1989), and reaffirmed in U.S. v. Eichman, 496 U.S. 310 (1990), has ruled that due to the First Amendment to the United States Constitution, it is unconstitutional for a government (whether federal, state, or municipal) to prohibit the desecration of a flag, due to its status as ``symbolic speech.'' However, content-neutral restrictions may still be imposed to regulate the time, place, and manner of such expression. If the flag that was burned was someone else's property (as it was in the Johnson case, since Johnson had stolen the flag from a Texas bank's flagpole), the offender could be charged with petty larceny (a flag usually sells at retail for less than USD 20), or with destruction of private property, or possibly both.