A smokescreen is a tactic of war to provide cover for troops to either attack or retreat, depending on the circumstances. On occasions, it can also be used to asphyxiate.
This week saw the National Party deploy one after it somehow managed to obtain some of the spending figures which will be in Thursday's Budget.
They merrily released them as both Labour and National MPs went into their weekly caucus meetings, and then watched the fog swirl.
A couple of hours later the smoke had reached its peak.
National released two further statements: The first was an announcement that MP Alfred Ngaro had bottled out of running away from home to set up his own political party.
The second was the recommendations – but not the findings – of a review the party ordered into its internal processes for dealing with situations such as harassment, bullying and mental health issues.
The party had previously refused to release any details about the review, including who was doing it.
It was presumably hoping the smoke from the rare and concerning release of Budget information would help obscure the two other stories, both of which related to its own internal cogitations.
That did indeed work to a degree.
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It is no small thing for Budget information to seep out before its intended release.
It is fair to say Minister of Finance Grant Robertson is kicking up more of a stink about it behind closed doors than he did in Parliament.
It was the second batch of secret information that had landed on National's desk this month after it was leaked the Cabinet paper on the cannabis referendum.
Bridges, who has suffered somewhat from leaks himself recently, was understandably jubilant to be the recipient of them instead of the victim.
As he crowed and Treasury and the officials scrambled to try to identify the hole in the Budget dyke, Robertson and Prime Minister Jacinda Ardern put on a determined show of dismissing National's figures as mere trivialities signifying little.
National's deputy leader Paula Bennett kicked off the fun, seeking leave for Bridges to take all questions on the content of the Budget rather than Robertson.
Amy Adams, National's finance spokeswoman, joined in a bit later, asking if this mysterious supply of confidential information to the Opposition in advance was part of Ardern's promise of transparency.
Ardern and Robertson did concede some of the figures National had were correct, but others were not. Neither would say which was which.
Things got far more serious at about 8pm on Tuesday night when Treasury head Gabriel Makhlouf issued a statement saying there was some evidence the Treasury website had been accessed.
Bridges has denied National did anything wrong, including hacking. However there is now a chance his victory could blow up in his face if it transpires the information was ill-gotten and National did not do its due diligence.
Robertson can take some solace in coming up with the best retort of the day.
Adams had asked if he would follow the lead of Labour Finance Minister Sir Roger Douglas, who offered to resign in 1986 after Budget documents were inadvertently sent to the NZ Herald ahead of time.
Robertson did not even pause: "In my life, I have made it my ambition not to follow what Roger Douglas does."
As for the stories released under the smokescreen, they do at least show Bridges has learned a valuable lesson about avoiding leaks.
Both Ngaro and the review were discussed in caucus that day. The results were released straight after that meeting.
The lesson he has learned is to release what happens in caucus before any of his colleagues have time to leak it.
As Ngaro would put it, leak unto others as they would leak unto you.