美军战前动员时为什么都大喊“Garry Owen”？

意思为"奋勇杀敌".
这是一首爱尔兰快步舞曲，在we were soldiers里面出现过。
舞曲起源不详，在18世纪后期流行起来，在皇家骑士团里很快受到欢迎。之后成为许多军队步兵和骑兵的进行曲，在许多战斗如拿破轮战争和克里米亚战争中都出现过，鼓舞过士气。
歌词：

1. Let Bacchus' sons be not dismayed
But join with me, each jovial blade
Come, drink and sing and lend your aid
To help me with the chorus:

Chorus:

Instead of spa, we'll drink brown ale
And pay the reckoning on the nail;
No man for debt shall go to jail
From Garryowen in glory.

2. We are the boys who take delight
In smashing limerick lamps at night,
And through the street like sportsters fight,
Tearing all before us
Instead of spa, we'll drink brown ale
And pay the reckoning on the nail;
No man for debt shall go to jail
From Garryowen in glory.

3. We'll break the windows, we'll break down doors,
The watch knock down by threes and fours,
And let the doctors wo