What argument in favor of the 26 amendment was considered crucial to its quick ratification

The 26th amendment was one that gave citizens who are 18 years or older the right to vote. One of the reasons behind its quick ratification was the Vietnam War. Considering that the law was passed officially in 1971, this was a time in which millions of American men were currently stationed in Vietnam or had served in this country during the Vietnam War. Many soldiers and citizens felt that it was unfair that these 18-20 year old men were drafted and forced to serve in the military despite not having any control over who is running the country. This was one of the jusitifications behind changing the voting age from 21 to 18.