The Xxcha ability states, "Immediately after a Political Card is drawn and read aloud, you may spend one Command Counter from your Strategy Allocation to cancel the card and force another Political Card to be drawn."
With Assembly and Assembly II, you rarely will draw and read aloud a Political Card. And with Political II, you never draw Political Cards at all.
Can the Xxcha veto Political Cards following the typical execution of Assembly, Assembly II and Political II?