“Thousands of rockets smuggled into Gaza. Could it be that hard to get a tactical nuke in there?”
Hamas in Damascus to the NE of Israel would be a better choice. Probably not too much Iron Dome coverage to the NE and quicker flight time. But I have no knowledge/purview on any of this.
Depending on the level of crazy, a ground blast could be used, in Gaza. No risk of a shoot-down.