An idiom for "saving tap water on drowning Titanic" situation [duplicate]

I'm looking for a phrase, that can be applied to the situation when someone attempts to resolve a big problem or minimize damage by performing minor, insufficient actions, or is micromanaging instead of dealing with relevant bigger issues. It suggests the actions that are useful per se, but turn out to be in vain while there are way more serious steps to be taken to deal with a challenge. Like, when you're trying to prevent a waste of tap water while your ship is drowning, or turning on the humidifier when your house is on fire.

Is there an idiom in English, that fits such kind of situations? Here are some more examples to provide clarification for its possible usage:

• An unprecedented drop of national economy was followed by the government's decision to mark the products of local manufacturers with conspicuous "wise choice!" labels.
• Our project is about to fail deadline, but Tom is busy with choosing fonts for its Powerpoint presentation instead of helping us to speed up.
• After receiving divorce papers from Jane's lawyer, Steve bought her flowers, hoping it will compensate the decade of neglecting his wife.

There is a well-known metaphor which concerns the Titanic, but I wasn't thinking of that one.

Often I have heard someone say: That suggestion sounds like rearranging the deck-chairs on the Titanic

It means that what is being proposed is a of minisule value in relation to the crisis in hand. It might prove a suitable response to any of the three circumstances you postulate.

Consider "a drop in the bucket" (or "a drop in the ocean"):

a very small amount in comparison to the amount that is needed

(http://idioms.thefreedictionary.com/a+drop+in+the+ocean)

For example, regarding the government you could say:

The government's decision to help the economy by marking the products of local manufacturers with conspicuous "wise choice!" labels is a drop in the bucket.

A similar expression is "a spit in the ocean".

In certain contexts "too little, too late" might work too:

not enough and not given soon enough to be useful

(http://idioms.thefreedictionary.com/too+little,+too+late)

It's broader in meaning as it also indicates that the measures were not taken soon enough, but I think it might work for the Steve and Jane situation, for example.

It's like pissing in the wind.

piss in the wind: to do something that is futile and counterproductive; to waste one's time doing something. McGraw-Hill's Dictionary of American Slang and Colloquial Expressions

It's like trying to keep a wave on the sand. Google Books

It's like pushing water up a hill [with a rake] Arabesk

This might be a bit different, but in some circles "straining out a gnat and swallowing a camel" would be well known and understood, from Matthew 23:24. That means ignoring the major problem and spending large amounts of effort to fix something that should be viewed as negligible.