Wrongo. It's actually the Official Mace of the House of Representatives, carried by the Sergeant at Arms. It is the supreme symbol of authority in the House, and usually sits next to the rostrum except in rare cases when displayed before an unruly member to restore order. It is a reminder that the use of force will be used if necessary.
In this case it was Nancy subtly reminding POTUS she had the authority to remove him from the chamber, using force if required by summoning the Sergeant at Arms.
https://en.wikipedia.org/wiki/Mace_of_the_United_States_House_of_Representatives
It also happens to be modeled from the Roman weapon called the Fasces (of FACISM fame):
https://en.wikipedia.org/wiki/Fasces
It is a symbol using many sticks bound together to make a stronger unit - from the many, one (e pleuribus unim).