help with code for custom post category

I know this topic has been covered a lot, but the code in the template I am using isn’t exactly the same as is covered in other forum posts, so looking for a little help.

I am trying to show only the category “American” from my Restaurants custom post list on my AMERICAN page. As it is now – the page is displaying ALL of the restaurants, not just the category I want. Here is the code I am using in my template, with my attempt at the category callout in bold:

<?php
/**
 * Template Name: Restaurants List American
 *
 */
?>

<?php get_header(); ?>
<?php $page_width = get_post_meta(get_the_ID(), 'wpl_sidebar_option', true); ?>
<div id="main" class="site-main container_12">
  <div id="primary" class="content-area ml <?php if ( $page_width != 'off' ) { echo 'grid_9'; } else { echo 'grid_12'; } ?>">
    <div id="content" class="site-content">

    <?php // Display the default content
      if ( $post->post_content != '' ) { ?>
        <?php while ( have_posts() ) : the_post(); ?>
          <article class="single">
            <div class="entry-content">
              <?php the_content(); ?>
            </div>
            <div class="clear"></div>
          </article>
        <?php endwhile;
      } // End displaying the default content
    ?>

    <?php $args = array( 'post_type' => 'post_restaurants','post_status' => 'publish', 'posts_per_page' => ot_get_option('wpl_restaurant_per_page'), 'paged'=> $paged); ?>
   <strong> <?php query_posts('category_name=American'); ?></strong>
      <?php $wp_query = null; ?>
      <?php $wp_query = new WP_Query( $args ); ?>
      <?php if ( $wp_query->have_posts() ) : while ( $wp_query->have_posts() ) : $wp_query->the_post(); ?>
        <!-- Article -->
          <article id="post-<?php the_ID(); ?>" <?php post_class('list'); ?>>
            <?php if ( has_post_thumbnail() ) {?>
              <figure>
                <a title="<?php the_title(); ?>" href="<?php the_permalink(); ?>">
                  <?php the_post_thumbnail('small-thumb'); ?>
                </a>
              </figure>
            <?php } ?>

            <h1 class="entry-header">
              <a title="<?php the_title(); ?>" href="<?php the_permalink(); ?>"><?php the_title(); ?></a>
            </h1>

            <div class="short-description">
              <p><?php echo wplook_short_excerpt(ot_get_option('wpl_restaurant_excerpt_limit'));?></p>
            </div>

            <div class="entry-meta">
              <a class="read-more-button fleft" href="<?php the_permalink(); ?>" title="<?php _e('Read more', 'wplook'); ?>"><?php _e('Read more', 'wplook'); ?></a>

            </div>
            <div class="clear"></div>
          </article>

      <?php endwhile; wp_reset_postdata(); ?>
      <?php else : ?>
        <p><?php _e('Sorry, no restaurants matched your criteria.', 'wplook'); ?></p>
      <?php endif; ?>

      <?php wplook_content_navigation('postnav' ) ?>
    </div>
  </div>

  <!-- Right Sidebar -->
  <?php if ($page_width != 'off') { ?>
    <div id="secondary" class="widget-area grid_3">
      <?php get_sidebar('restaurants'); ?>
    </div>
  <?php } ?>

  <div class="clear"></div>

</div><!-- #main .site-main -->
<?php get_footer(); ?>