(Editor's Note: President Trump announced in a Dec. 23 tweet that Deputy Defense Secretary Pat Shanahan would take over as acting defense secretary on Jan. 1 , assuming the role two months earlier than Secretary Jim Mattis' planned departure on Feb. 28.) Defense Secretary Jim Mattis will step down from his position at the end of February, telling President Trump in a resignation letter sent last week that he should have a Pentagon chief whose views "are better aligned"...
