That's not what I got out of your article Kukri:

In those times, folks often recycled good older melodies to use with new lyrics (for example, Maryland's state song uses the melody from "O Tannenbaum"), so no one minded that Scott Key used "To Anacreon in Heaven." Of course recycling melodies still happens today. Consider "The Barney Song," which uses the melody for "This Old Man." OK, so maybe you're not watching Barney so much anymore. How about Weird Al Yankovic's treasure chest of songs including "Smells like Nirvana" or "It's all about the Pentiums"? But even Weird Al knows, to recycle melodies today requires the use of finely-honed musical skills and the services of an excellent lawyer.

Key's lyrics circulated as a handbill, then were published in a Baltimore newspaper on Sept. 20, 1814. The song was designated the U.S. national anthem by executive order of President Woodrow Wilson in 1916. Following a 20-year effort during which more than 40 bills were introduced to Congress, the order was finally confirmed by Congress in 1931.
In other words, the melody for the Star Spangled Banner was borrowed from another, a fairly common practice in the 18th & 19th century. The lyrics, however, are as Key wrote them. Hmm....

And before anyone brings up "My Country T'is of Thee" versus "God Save the Queen", you have to remember, we were at war with Britain when it was written... which only proves my point. Co-opting our national anthem and changing the lyrics to suit their agenda proves that Latino immigrants are not interested in becoming American.