"Give me 26 soldiers of lead and I shall conquer the world" refers to the 26 letters in the alphabet that a printer would have in a typeset.
This quote refers to the power of the printed language, which is still true today. In the 2016 American Presidential Election we saw the power of "fake news" used by the Russian Government against American citizens. Language is, quite simply, still an effective tool for persuading and taking over the world.