Today there won't be much issues, I'm talking about a reality in which your Government (doesn't matter if it's the US, UK, Germany or China) is not only not helping you to build strong crypto (which they always done so in the past), but actually is working against you.
How easy would it to work on open encryption software if we'll have to revert to the Pre Bernstein V. United States era (which wasn't so long ago) and one that might actually be more heavily regulated than (restriction on actual work on encryption and related field rather than exporting software) before? Heck Phil Zimmermann almost ended up going to jail when PGP was "leaked" outside of the US, and this isn't East Germany, this is the US in the mid 90's.