Seven years, six months, 23 days, three Iranian presidents and two American presidents later, Iran has reached a deal with the six world powers — the United Kingdom, China, France, Russia, the United States and Germany — to contain its nuclear program. Overcoming three and a half decades of diplomatic hostility takes time, and this deal was certainly no exception . But before speculation runs wild on how many barrels of oil will now be dumped on the markets, how much cash and weapons Iran can funnel to its militant allies, and all the ways Iran could end up acquiring a nuclear weapon anyway, allow us to lay out what actually matters and is likely to develop in the years ahead as a result of this deal. First, let's get the timeline straight.