<iframe width="580" height="385" src="https://www.youtube.com/embed/3bqVaabsQJk" frameborder="0" allowfullscreen></iframe> <br>The U.S. and Russia are building up their forces around Ukraine as the threat of war escalates. Charlie D'Agata reports. <br><a href="https://www.youtube.com/watch?v=3bqVaabsQJk">source</a>