How do I center the nav buttons?

My buttons are now nicely centered, but it's created a new issue. See screenshot. It only does this on the "About Us"  and "Contact Us" dropdowns. The others, coded exactly the same, work fine.

I tried adding:

.dropdown-menu li {

  text-align: left;

}

And I tried looking at the code on Chrome but I just can't see

1) Why some lists that are longer display perfectly while two others, coded exactly the same, don't, and

2) Why the Divider has disappeared (not a huge deal, but it's supposed to be there)

Code:

   <!-- Navigation -->   

<nav class="navbar navbar-default dkblue col-lg-12 col-lg-offset-0">

    <!-- Brand and toggle get grouped for better mobile display -->

    <div class="navbar-header">

      <button type="button" class="navbar-toggle collapsed" data-toggle="collapse" data-target="#defaultNavbar1"><span class="sr-only">Toggle navigation</span><span class="icon-bar"></span><span class="icon-bar"></span><span class="icon-bar"></span></button>

</div>

    <!-- Collect the nav links, forms, and other content for toggling -->

    <div class="collapse navbar-collapse dkblue" id="defaultNavbar1">

      <ul class="nav navbar-nav bg-primary">

        <li> </li>

        <li> </li>

        <li><a href="#" class="whitetext">Home</a></li>

        <li class="dropdown"><a href="#" class="dropdown-toggle whitetext" data-toggle="dropdown" role="button" aria-expanded="false">About Us<span class="caret"></span></a>

          <ul class="dropdown-menu" role="menu">

             <li><a href="#">Our History</a></li>

            <li class="divider"></li>

            <li><a href="#">Our Core Values</a></li>

            <li class="divider"></li>

            <li><a href="#">Board of Directors</a></li>

            <li class="divider"></li>

            <li><a href="#">Kairos Foundation</a></li>

            <li class="divider"></li>

            <li><a href="#">News</a></li>

            <li class="divider"></li>

            <li><a href="#">Videos</a></li>

          </ul>

        </li>

        <li class="dropdown"><a href="#" class="dropdown-toggle" data-toggle="dropdown" role="button" aria-expanded="false">Our Programs<span class="caret"></span></a>

          <ul class="dropdown-menu" role="menu">

             <li><a href="#">Kairos Inside</a></li>

            <li class="divider"></li>

            <li><a href="#">Kairos Outside</a></li>

            <li class="divider"></li>

            <li><a href="#">Kairos Torch</a></li>

            <li class="divider"></li>

            <li><a href="#">Our Impact</a></li>

            <li class="divider"></li>

            <li><a href="#">Testimonies</a></li>

          </ul>

        </li>

        <li class="dropdown"><a href="#" class="dropdown-toggle" data-toggle="dropdown" role="button" aria-expanded="false">Volunteer<span class="caret"></span></a>

          <ul class="dropdown-menu" role="menu">

             <li><a href="#">Ways to Serve</a></li>

            <li class="divider"></li>

            <li><a href="#">Creating Agape</a></li>

            <li class="divider"></li>

            <li><a href="#">Kairos Kalendar</a></li>

            <li class="divider"></li>

            <li><a href="#">Interest Form</a></li>

          </ul>

        </li>

         <li class="dropdown"><a href="#" class="dropdown-toggle" data-toggle="dropdown" role="button" aria-expanded="false">Where We Serve<span class="caret"></span></a>

          <ul class="dropdown-menu" role="menu">

             <li><a href="#">35 States</a></li>

            <li class="divider"></li>

            <li><a href="#">9 Countries</a></li>

          </ul>

        </li>

        <li class="dropdown"><a href="#" class="dropdown-toggle" data-toggle="dropdown" role="button" aria-expanded="false">Contact Us   <span class="caret"></span></a>

          <ul class="dropdown-menu" role="menu">

             <li><a href="#">Email</a></li>

            <li class="divider"></li>

            <li><a href="#">Write</a></li>

            <li class="divider"></li>

            <li><a href="#">Phone</a></li>

  </ul>

        </li>

        <li class="dropdown"><a href="#" class="dropdown-toggle" data-toggle="dropdown" role="button" aria-expanded="false">Donate<span class="caret"></span></a>

          <ul class="dropdown-menu" role="menu">

             <li><a href="#">Donate Online</a></li>

            <li class="divider"></li>

            <li><a href="#">Cash Gifts</a></li>

            <li class="divider"></li>

            <li><a href="#">Planned & Estate Gifts</a></li>

          </ul>

        </li>

      </ul>

    <!-- /.navbar-collapse -->

  </div>

  <!-- /.container-fluid -->

</nav>

</div>