<p>Not every job at NASA needs a security clearance. Only things that are sensitive to national security need a security clearance, and NASA does a lot more than that. They do a ton of just fundamental aerospace research. Boeing only requires a clearance if you are working in a select few jobs in the defense branch. The majority of people there don’t even have a clearance though. Airbus doesn’t have any engineering operations in the United States, so that is a non-issue, although I believe they have plans to open a manufacturing facility for A320’s over on this side of the pond sometime soon. Their engineering operations take place over in the UK and France and other European countries.</p>
<p>The bigger obstacle is that a lot of jobs on the defense side of things require U.S. citizenship. That is a lot more common than requiring a security clearance.</p>