My rewording:
In July 1946, an article proposed that the West adopt a policy of "containment" upon the Soviet Union. The author, George Kennan, a leading official in the construction of the U.S embassy, located in Moscow in 1943, had pushed for the United States to prevent Soviet expansion with many different methods. In fact, George Kennan was utterly convinced that if the Soviet Union could not expand further that the nation's social system would begin to deteriorate.
Grammar corrections on your version: If you wish to keep what you have right now, I can help you out with some of the technical details. For example, it's article, not "artical"; sentences should begin with capitals.
Here's a corrected and slightly altered version of what you have:
In July 1947, an article was written and released by George Kennan which proposed that the West adopt a policy of "containment" towards the soviet union. Though he set up the us embassy in Moscow during 1943, he called on the United States to begin to prevent soviet expansion. George was convinced that if the soviet union failed to expand, the social system would eventually break down.
