Any of the many intercepted devices can exploit and steal your Bitcoins through the NSA and people who figure out the backdoors.
Oh dear. Logic failure. It long been argued that "they" wouldn't engineer back doors for the very good reason that if they were discovered lots of very important government/commercial information would be compromised. A leak could blow open all security. Now lets look to a leak, Snowden, and its evident that NSA etc have focused on interception. Why would you try interception if you've got back doors in everything? You would not, so in effect Snowden's revelations have shown that NSA have not got back doors written into systems.
if you want some bitcoin related evidence that NSA are hopeless. look at the DPR news. the NSA had to send DPR's wallet over to the UK's intelligence office to brute force the password. the NSA cant crack encryption, nor do they have the computer power or skill to bruteforce.
Though i've no doubt to us Brit's fine IT skills, its passed to UK so its nice and legal. We do the same the other way.