The metric system is not only universally used (except for the US and maybe Myanmar) but it is much easier than the English system. The metric system is based on decimals and so there is no need to deal with fractions or ridiculous things like 16 oz. in a pound or 5280 feet in a mile. Most of the resistance to it, I believe, lies in the erroneous idea that one would have to constantly convert between the two systems. Once you get into metrics, you simply stay there and never convert again.
We do have some metrics in the US, however. Beverages come in liter bottles (or parts thereof) and every drug addict knows what a kilogram is.
