When I run your code it gives the following error in Firebug:
Error: Bootstrap's JavaScript requires jQuery
This is because jQuery isn't loaded properly in your code.
You can (quick) fix this by adding http:// or https:// to the jQuery URL.
<script src="http://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
or
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
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