Like a mosquito hitting a semi-truck

I was just listening to the Kojo Naambdi show on WAMU (local NPR affiliate station) during my lunch break, when I was amused by a somewhat misguided analogy. One segment of the show was about a space probe that NASA launched to crash into a comet. The part of the spacecraft that will actually impact the comet was referred to as the 'bullet.'

In trying to put the comet and bullet into perspective, to assuage fears that this will somehow split the comet in two or redirect its orbit so that it could hit the Earth, Kojo's expert guest said that there was no danger, and that it was basically, and I quote, "a David and Goliath type of thing."

In my recollection, the bullet (rock) in David and Goliath had quite an effect on that story's comet (Goliath's head). So, according to Kojo's guest, the end is nigh.

To be fair, he also used the analogy that is the title of this post earlier in the conversation.