Fontawesome in polymer 2

When I try to load the fontawesome script into a polymer 2 component I can not see the icons. This is what I do:

<link rel="import" href="../../bower_components/polymer/polymer-element.html">
<script defer src="https://use.fontawesome.com/releases/v5.0.6/js/all.js"></script>

<dom-module id="mi-icono">
  <template>
    <i class="fas fa-address-card"></i>
    <i class="fas fa-trash-alt"></i>
  </template>

  <script>
    /**
     * @customElement
     * @polymer
     */
    class MiIcono extends Polymer.Element {
      static get is() { return 'mi-icono'; }
      static get properties() {
        return {
          icono : String
        };
      }
    }

    window.customElements.define(MiIcono.is, MiIcono);
  </script>
</dom-module>