It's my turn (I am the US), and I play a card with an operational value of 4 points. The event is a Russian one and I don't want the event to occur so I use it for the space race which I haven't done this turn yet. It costs 2 operational points to attempt to move on the space race ladder, however I roll a 6 and so my attempt fails. Can I try it again? I have only used 2 operational points and still have two left. The rules say I can only use one card per turn for the space race which makes sense if you have an Ops of 3,2 or 1, but in this instance I am using only one card with an operational value of 4.
Short answer: No. It was your choice to use the card that way. If you wanted to use all of the ops, you had to let the event happen.