They captured the Amplifier to catch a breath of fresh air and think on their next move. The Allies intended to launch a counter offensive in North America but they lost the backup battery for the Paradox Engine and their movements are now limited, so they want to strike where they'll deal the most damage, which is the Antarctica base.
So now that the Allies are pushing in towards the South Pole, what lies in wait for them? Libra and Rahn are on their way to the Tower while the Russians are preparing to launch towards Moscow from the moon. What else is new here?