Is "A mighty fortress is our God" anti-Catholic?

Question

So there's a hymn called A mighty fortress is our God (Ein feste Burg ist unser Gott), written by Martin Luther; there's also a famous version by J. S. Bach. It is a call to arms against the devil, and is particularly associated with the Reformation.

The lyrics are full of references to Satan (der alte böse Feind, der Fürst dieser Welt, der Teufel); the Bach cantata has a few more (zum Kriege wider Satans Heer, treib Welt und Satan aus). That's all fine. What I was wondering about was the extent to which these should be read as references to the Catholic Church and the Papacy. After all, Luther wasn't shy about that in his prose works - calling the Pope an Antichrist, Devil, Satan, Satanissimus, etc., and speaking in martial terms about the conflict between them, where Rome is presented as being part of the devil's captured territory.

1. Were the devil-references in the hymn originally intended to be about Luther's Catholic opponents?
2. Does the hymn come across today as anti-Catholic? (And therefore, to be avoided.)

_{For context, in my congregation we are perpetually anxious about martial metaphors and sectarian divisiveness. We did do Onward Christian soldiers last year, but only after an explanation/rationale from the pulpit. We'd be happy to sing about the devil being our enemy, but not at all happy to sing against our brothers and sisters in Christ.}

2nd Verse

“And though this world, with devils filled,
Should threaten to undo us;
We will not fear, for God hath willed
His truth to triumph through us.”

Answer 1

The estimated date of Luther composing this hymn is between 1527-1528. In the summer of 1528 the city Luther lived in fell to the bubonic plague. Instead of evacuating Luther chose to risk disease and stay ministering.

Some scholars have argued that during these weeks of the plague, in which also the tenth “anniversary” of the posting of The Ninety-five Theses fell, Luther composed his A Mighty Fortress is Our God (Luther's Works 49.175)

I searched Luther's works and their is no direct links of his identification of the Pope with the antichrist, or other anti-catholic implications to this hymn.

The copy I have is entitled 'Our God is a castle strong'. The only place where it is likely that Luther may have personally thought of the papacy was here:

If they take our life,
Wealth, name, child and wife—. Let everything go:
They have no profit so;
The kingdom ours remaineth.

However even under fears that the Pope would have Luther murdered for his faith, the plague may have been more forefront in his mind.

Answer 2

1. Luther was not intending the song to be about his Catholic opponents. As Mike pointed out, Luther did not have that sort of hostile view of the Church. The song makes reference to scripture throughout. It is based primarily on Psalm 46 (below), and the particularly "militant" parts ("the body they may kill") are simply references to Job. I can't imagine that Luther would've even had enough thought to think of his opponents, with all the thinking he was doing about scripture while composing this.

2. If it came across as anti-Catholic today, it wouldn't be in Catholic Hymnals. There is of course some association with Luther, but strong sentiments are generally not there today. If you search through Catholic forums, you'll see that the hymn is beloved by many Catholics, and though some do feel uneasy, the fact is that the hymn is sung with approval by Catholics during Mass. From Wikipedia:

   The hymn is now a suggested hymn for Catholic Masses,[7] appearing in the second edition of the Catholic Book of Worship, published by the Canadian Conference of Catholic Bishops, though this is not without controversy. Its enduring popularity in Western Christendom has breached boundaries set in the Reformation.

If you are concerned, perhaps precede the hymn with a reading or explanation of Psalm 46, or Job.

Psalm 46
1 For the leader. A song of the Korahites. According to alamoth.

I
2 God is our refuge and our strength,
an ever-present help in distress.
3 Thus we do not fear, though earth be shaken
and mountains quake to the depths of the sea,
4 Though its waters rage and foam
and mountains totter at its surging.

II
5 Streams of the river gladden the city of God,
the holy dwelling of the Most High.
6 God is in its midst; it shall not be shaken;
God will help it at break of day.
7 Though nations rage and kingdoms totter,
he utters his voice and the earth melts.
8 The LORD of hosts is with us;
our stronghold is the God of Jacob.

III
9 Come and see the works of the LORD,
who has done fearsome deeds on earth;
10 Who stops wars to the ends of the earth,
breaks the bow, splinters the spear,
and burns the shields with fire;
11 “Be still and know that I am God!
I am exalted among the nations,
exalted on the earth.”
12 The LORD of hosts is with us;
our stronghold is the God of Jacob.