Is a wall along the US-Mexico border realistic? CNN's Ed Lavandera reports. <script type='text/javascript' src='http://z.cdn.turner.com/cnn/van/resources/scripts/van-widgets.js'></script> <div data-cnnvansinglewidget data-affiliate='gantdaily' data-videoid='world/2016/11/11/trump-mexico-wall-lavandera-pkg.cnn' data-size='auto' data-autostart='true'></div>