<!DOCTYPE html>
<html lang="ja">
<style>
svg{
 border:solid 1px;
 }
 </style>
<head>
  <meta charset="utf-8">
  <title>D3.js(Force Layout)の練習</title>
</head>
<body>
  <script src="http://d3js.org/d3.v3.js" charset="utf-8"></script>
  <script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
  <script src="https://cdnjs.cloudflare.com/ajax/libs/d3/3.4.11/d3.min.js"></script>



  <script>
  function pointer(){
     var object = document.getElementById('object');
   if (object.contentDocument)
   var svgdoc = object.getSVGDocument();
   var svgelm = svgdoc.documentElement.style.cursor='pointer';
 }


  var w = 800;
  var h = 800;

  var nodes = [];
  var links = [];
  var xlink = [];
  var link2 = [];


  var url = "https://ajax.googleapis.com/ajax/services/feed/load?v=1.0&q=http://feeds.feedburner.com/hatena/b/hotentry&num=-1";
  var proxy_url = "http://allow-any-origin.appspot.com/" + encodeURIComponent(url);


  function for_each(array, func){ Array.prototype.forEach.call(array, func); }

  function get_html(callback){
   var hatena_hotentry_url = "http://b.hatena.ne.jp/hotentry";
   hatena_hotentry_url = "http://allow-any-origin.appspot.com/"
    + encodeURIComponent(hatena_hotentry_url);






   /*// var hatena_hotentry_url = "./hatena_hotentry.html"
  */
   var req = new XMLHttpRequest();
   req.open("GET", hatena_hotentry_url);
   req.onreadystatechange = function() {
    if (req.readyState === 4 && req.status === 200) {
     callback(req.responseText);
     req = undefined;
    }
   };
   req.send(null);
  }

  function html_to_relation(html){
   var doc = new DOMParser().parseFromString(html, "text/html");
   var error_tags = doc.getElementsByTagName("parsererror");
   if(error_tags.length){
    console.log("error: ", error_tags);
    return [["Parse error", "Maybe HTML is broken"]];
   }

   var relation = []; /*// [["name", ...], ...]
  */ var entry_elms = doc.querySelectorAll(
     "[data-track-section='default'] .entry-contents");
   for_each(entry_elms, function(entry_elm){
    var entry_link_elm = entry_elm.querySelector(".entry-link");
    if(!entry_link_elm){ return; }

    var name_array = [];
    relation.push(name_array);
    name_array.push(entry_link_elm.title);

    console.log(entry_link_elm.href)

    var entry_meta_elm = entry_elm.nextElementSibling;
    if(!entry_meta_elm){ return; }
    for_each(entry_meta_elm.querySelectorAll("a.tag"), function(tag_elm){
     name_array.push(tag_elm.textContent);
      name_array.push(entry_link_elm.href);
    });
   });

   return relation;
   }






  function relation_view(relation){
   /*document.getElementById("view").textContent
           = JSON.stringify(relation, undefined, 2);
  */



  /* d3.json(proxy_url,function(error,json){
  if(error){
   return console.warn(error);
  }

  var feeds = json.responseData.feed;

  for(var x = 0;x < feeds.entries.length;x++){
   var href = {"url": feeds.entries[x].link};
   xlink.push(href);
  };

  }); */





   for(var i = 0;i<relation.length;i++){
      if(i+1 < relation.length){
          var num ={"source":  i ,"target": + (i+1) };
      }else{
          var num ={"source":  i , "target": 0};
      }
      var list = {"label": relation[i][0]  , "url": relation[i][6]  };
              nodes.push(list);
            links.push(num);


   }

   console.log(nodes)




    var force = d3.layout.force()
          .nodes(nodes)
          .links(links)
          .size([w, h])
          .linkStrength(0.1)
          .friction(0.9)
          .distance(200)
          .charge(-30)
          .gravity(0.1)
          .theta(0.8)
          .alpha(0.1)
          .start();

    /*console.log(nodes)*/

    var svg = d3.select("body").append("svg").attr({width:w, height:h});

    var link = svg.selectAll("line")
          .data(links)
          .enter()
          .append("line")
          .style({stroke: "#ccc",
                  "stroke-width": 1});


    var node = svg.selectAll("a")
     .data(nodes)
     .enter()
     .append("a")
     .attr(":xlink:href",function(d){return d.url;})
     .append("circle")
     .attr({r:20,opacity:0.5})

     .style({fill:"red"})
     .call(force.drag);

     var label = svg.selectAll('text')
      .data(nodes)
      .enter()
      .append('text')
      .attr({"text-anchor":"middle",
         "fill":"black"})
      .attr({'pointer-events' : 'none'})
      .style({"font-size":11})
      .text(function(d){return d.label;});




     force.on("tick", function() {
          link.attr({x1: function(d) { return d.source.x; },
                     y1: function(d) { return d.source.y; },
                     x2: function(d) { return d.target.x; },
                     y2: function(d) { return d.target.y; }});
          node.attr({cx: function(d) { return d.x; },
                     cy: function(d) { return d.y; }});
          label.attr({x: function(d) { return d.x;},
               y: function(d) { return d.y }});

  })
  }



  get_html(function(html){ relation_view(html_to_relation(html)); });


  </script>
</body>
</html>

上記のプログラムでforceモデルを実装していますが上手くリンクが動作しません。
リンク自体はデベロッパーツールで正しく設定されていることが確認できるのですがクリックすることができません。
textに'pointer-events' : 'none'を設定しているのですがこれは正しく設定できていないのでしょうか？
お力添え宜しくお願いいたします。