If the US is ahead on the Space Race track, play this card to search through the discard pile for a non-scoring card of your choice. Event occurs immediately.
A card of your choice. But there's no reference to "you can play, so I guess the event occurs unless the discard pile is empty.
Very fringe case, but strange things happen at TS. Let's say:
Discard pile gets empty somehow.
USSR plays muslim revolution (for example) for ops.
US plays starred event/space race/USSR card for ops.
USSR plays star wars (and US is ahead on space race)