Final answer:
The literary technique used in the given statement is a simile, which compares two unlike things using 'like' or 'as' to highlight the control one character has over another.
Step-by-step explanation:
The literary technique used in the statement “…wedging his tense arm imperatively under mine, Tom Buchanan compelled me from the room as though he were moving a checker to another square” is known as a simile. This is a figure of speech that compares two different things using the words 'like' or 'as'. In this case, the movement of one character by another character is compared to the action of moving a checker piece on a board, highlighting the control one character has over another in a very visual and relatable way.