Question

I would like to know the feasibility of certain kinds of attacks. To be clear, assume the target is a high-level priority of the NSA.

1. Is an OS such as tails useless against root-kits/keyloggers, etc? As far as leaving no trace on computer?

2. Could such malware/root-kit be transferred to a computer which has never been connected to the internet, has its physical wifi card removed, etc., by transferring pdf files to that computer?

3. Could using the same usb from offline computer to online computer transfer information/files without my knowledge? (ie. malware that loads files onto USB without my consent)?

4. This one may take some specifics. Let us suppose that when I run Tails OS there is some incompatibility with hardware/software that does not allow Tails to "see" my wifi card, and thus, in order to access the internet I have to use a usb-wifi card. Could a sophisticated adversary with full remote access/control to my normal OS/machine, "see" my Tails sessions via remote access to my normal OS and WiFi card?

5. What is a defense against remote access to my machine?

Any other information/suggestions welcome.