Quote Originally Posted by it-ogo View Post
USA had several problems with their space shuttles and found them too complicated and unreliable. They stopped using shuttles, which were their actual technology for the space launching. Now they are developing alternative but it will take some time. On the other hand Russia (almost) always used old-good Soyuz rocket which is simple and reliable and much like first space rockets. So USA now use Russian rockets and facilities for their launches.

This wiki article discusses one of the possible replacements for the space-shuttle, the Ares I rocket. But as the article notes, the projected cost per launch (that is, AFTER the research & development costs) could be around $1 billion -- versus about $150 million to get three US astronauts into orbit on a Russian Soyuz rocket!

I'm not exactly sure why NASA chose not to go back to the proven technology of the Saturn V rockets after the retirement of the Space Shuttle -- I suspect there's a complex mix of technical, budgetary, and stupid-politics reasons.