Why don't we have weapons in orbit 'cus the ChiComs certainly don't care about the pact we signed with the UK and the USSR. I know that they've signed it too, but I really can't trust them and I think that they will push the envelope as much as they can and cross the line if they think that they can get away with it. The Chinese have based much of their war planing on fighting the US. They know that our military is very information driven and somewhat dependent on satellites for much of that information - mainly GPS and communications. The new cold war is with China and no one has made any real effort to push back.
On the other hand, it is nice to say that we are working with others on peaceful research and have moved past such things.