Esther 5 describes how Haman was incensed by Mordechai’s arrogance and couldn’t tolerate his existence anymore. V. 10 describes how Haman convened with his cronies to plot and devise a plan how to deal with Mordechai. Then (v. 14) Zeresh pipes up with a (not-so) brilliant idea:
Then Zeresh his wife and all his friends said, “Have a pole made 50 cubits[g] high, and then in the morning speak to the king and have Mordecai hanged[h] on it. Then go with the king to the banquet happy.” This advice pleased Haman, and he had the pole made.
Zeresh’s plan strikes me as downright stupid. Why would the king agree to hang Mordechai, a good and loyal citizen, on a pole?
Furthermore, the text tells us that Mordechai was a respected government official who sat at the king’s gate (see v. 9). Why, in heavens name, would the king execute Mordechai just because Haman dislikes him. Zeresh does not even seem to address this concern!
Now one might suggest that Haman was so loved by the king that he was given free reign over his kingdom (and was able to hang whomever he pleased), but this only intensifies the problem; namely, what kind of advice was Haman looking for, and how did Zeresh's advice play a role in solving her husband's problem (whatever that problem may have been)?
The form of execution sounds trivial compared to the bigger problem: how to get the King to execute Mordechai; yet the text seems to be focused on this trivial matter (hang or impale on a high 50 cubit pole) but ignore the elephant in the room!
So my questions in summary: What in Zeresh’s input did Haman find so appealing? What was Haman’s dilemma and how did Zeresh solve it?
P.S. To clear up some confusion here: I'm not interested in what Zeresh thought or what went through her mind when she spoke (i.e., that she wanted to placate her husband or other suggestions that were posted by other users), I'm only interested in understanding the authorial intent. What did the author intend when he wrote down Zeresh's response (is the author satirizing the incident, portraying Haman's family as shortsighted, or is he presenting a real and solid plot), how did he intend to portray her (as a conniving sly woman, or as a foolish dope), why did the author feel it was important to include, and most importantly, how did it play a role within the larger framework of this complex narrative.