Why does Aragorn let Frodo go?

[Essex]

Originally Posted by Tuor in Gondolin

You bring up an interesting point here. In the book Aragorn intended to go with Frodo (considering also including Gimli) and it was Frodo's decision to leave. But PJ apparently wanted a direct confrontation presumably for his "story arc" of Aragorn) which unfortunately again lessened the gravitas of movie Frodo to a passive person reacting to others.

that's unfair on PJ's Frodo. He had already decided what to do before Aragorn turned up. Aragorn did not force him or cajole him to go to mordor. he just told frodo that he would have followed him but could not. It was Frodo's decision to leave ON HIS OWN EVEN WITHOUT SAM as in the book. What's more movie Frodo also warned merry and pippin not to follow him. SO HE IS NOT BEING PASSIVE.

I have always struggled with book Aragorn's decision to leave frodo and sam just to follow merry and pippin. The film actually gives aragorn a reason for NOT following frodo, and I think this works quite well.