tempest in a teacup

A tempest in a teacup is a phrase used when referring to an argument or a disagreement which has taken place about a minor matter. This is another way to say that the thing you are disagreeing on, or arguing and fighting about, is not a big deal. This thing which you intend on arguing about so angrily is only a very minor matter, and more important things should be focused on rather than these meaningless fights.