Great Britan exits the EU

The strength of the USA has been its large population and resources base. The UK is considered the World's 5th largest economy and was the EU's second largest. I imagine they will be able to maintain trade with the EU, but I don't think it will be the same favorable treatment the UK has received up to now. Additionally, the fact that Scotland and Northern Ireland both voted to remain in the EU has already prompted calls for a re-vote of the failed 2014 Scottish independence referendum as well as calls for Northern Ireland to leave the UK to stay in the EU. The end result of the BREXIT vote could be the diminution of the UK into England & Wales.
Additionally, the vote appears to have been driven along age lines in that younger voters wanted to stay in the EU and older voters seemed to long for days past and an Independent UK. Under the Lisbon Treaty, unlike the US Constitution, EU member states have the stated right to remain or stay in the EU and have roughly two years to work out the details of how they exit and future relations with the EU. Given the age difference in support for Leaving the EU, I wouldn't be all that surprised to see a re-vote on EU membership somewhere down the line.
There was a pro-leaving Conservative MP on the BBC who was assuring people that there would be minimal problems even though the BBC commentators were talking about how quickly the British Pound seemed to be affected by the unexpected Leave outcome. She also maintained that David Cameron would remain Prime Minister and lead the UK thru its exit negotiations, even though he had opposed leaving the EU.
Things will be interesting for the next few years.