I recall the ROTC Building but I didn’t know about the chant.The combination of the arson and that chant would have made a reasonable Guardsman fearful and,perhaps,a bit jumpy.And that goes for Officer *and* Enlisted.
We should know that the Guard did not just show up on campus because a few students might make a few "anti-war" signs and statements.
There was real trouble in Kent, the city as well as the campus, as you documented.
Days of trouble (which included street violence if I remember correctly) in the community forced Governor Rhodes to respond to urgent requests and send help for the city police and the university.
And Kent state was just the last in a long line of campus riots, bombing and burning...I was raising my family through those times and thought more than once that this country will not survive what was going on...and police and NG were for the most part sitting ducks with orders not to stop the riots or shoot back...the inner citys across the country were also burning, looting and rioting along with a couple of radical catholic priests that went after recruiters for the military.....