Final answer:
This allusion refers to 'The Wizard of Oz' where Dorothy clicks her heels together three times to return to Kansas. It symbolizes a yearning to go back to a better, simpler time or state of being.
Step-by-step explanation:
The allusion, "If I could click my heels together and go back to the way things were, I would do so in a heartbeat," comes from the classic American film The Wizard of Oz.
In this film, the character Dorothy Gale discovers that she can return home to Kansas from the magical land of Oz by clicking her heels together three times while saying, "There's no place like home."
The allusion refers to a desire to return to a former state of being or to a better or simpler time. It taps into the idea of longing for the comfort and familiarity of home, much like Dorothy did in her adventures.