Yes, I was just reading this passage from the book of Joshua yesterday. The Captain of the Host of the Lord is Jesus Christ himself, before He came to earth in human form. This must be Christ, the Lord's angels wouldn't accept God's children worshipping them. There are many instances of the per-incarnate Christ interacting with His people (these are called theophanies). It's all very interesting and shows further evidence for the belief that we serve a very personal and relational God, even in the Old Testament times.