In a similar way, many do not understand how big our planet is - only a misunderstanding of the scale of Earth would lead somebody to believe we could actually affect the climate.
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I disagree.
We could certainly affect the climate or more accurately, the weather, if we put in the effort with the right technique.
In a very localized (weather) sense, that is true. (See "Tokyo Firestorm" -- but we would soon run out of energy to continue the effect...