# Do we need sulfuric acid to make TNT?

Do we actually need sulfuric acid to make trinitrotoluene? TNT's formula is $$\ce{C7H5N3O6}$$ so we just need toluene($$\ce{C7H8}$$) and nitric acid($$\ce{HNO3}$$). If we mix them we get TNT, and water($$\ce{H2O}$$)

$$\ce{C7H8 + 3HNO3 → C7H5N3O6 + 3H2O}$$

But Wikipedia states we need sulfuric acid. Why?