It's long been my view that there is an ideal tax rate, which is not defined necessarily by the largest amount of tax revenue, but rather by the largest GDP which results from government spending.
In other words, IMHO we need a certain amount of government spending on infrastructure, defense, and general public requirements. Spend less than that, the roads crumble, bridges fall down, hurricanes or tornados don't get predicted, etc. Spend too much and the tax burden becomes too restrictive.
Many folks are too quick to dismiss all government spending as wasteful and all government projects as boondoggles. Yet history has several shining examples of government projects which spurred this nation's growth, providing a phenomenal return on investment (and which private industry couldn't or wouldn't do). The Transcontinental Railroad completed in 1869 is a good example; it opened up the west for development.
The Panama Canal is another. Private industry tried but failed; massive American government funding (highly criticized at the time) completed what has now become one of the most important waterways in the world (and it was vital during World War 2).
The Interstate Highway System of the 1950's and 1960's is yet another. Again, it took massive government funding, but the interstates are vital for American business; not just for the truckers or regular drivers, but look at the number of businesses that grow up around Interstate interchanges. Private industry could not achieve the success of the Interstate system.
Again, I do believe that too much taxation will choke off the economy as well. There must be a balance; merely screaming that "taxes are too high and should be cut" is unrealistic.