I remember that the media image given of Bastogne ( movies and such ) give the indication that most GI units pulled back at first and the 101 ran in to fill back the lines. Not to take away anything from the 101 and other units called in , but a lot of GIs did not retreat and did stand firm . I remember one such unit of a small group of men on some high ground , in positions not too unlike the above picture , that held up the Germancolumn with little more than what was shown here for a day or so . Till most were killed or wounded and ammo gone.
Indeed , brave men.
Chris