Three identical AJAX button handlers in three views
I was able to get rid of the duplicate code by using event delegation.  I changed my event listener to:

$('#taglist').on('click', '.remove-tag-button', function () {
    $.ajax({
      type: "POST",
      data: {id: &lt;%= @item.id %&gt;, tag: $(this).data("tag-name")},
      url: "/remove_tag"
    });
  });