Laptops certainly have more security potential than desktops, but getting that potential is pretty inconvenient. For one you can keep your laptop on you at all times, with a desktop the best you can do is keep your boot loader on a USB or CD that you keep with you at all times. In the case of Desktops, this will only protect you from evil maid attacks that replace your boot loader with a bugged version in order to steal encryption keys. With a laptop it will protect you from hardware keyloggers, which can be a real threat against desktops. You can try to protect a desktop from such attacks if you have a surveillance system , such as cameras and door alarms, that can alert you if your home is intruded on while you are away, and also if you desktop has been modified. You can use TPM modules to protect from hardware tampering some as well. But nothing is as safe as always taking your computer with you and keeping it near by at all times. Another advantage laptops have is the ability to access random wireless access points. If you do this correctly it can extremely change your anonymity dynamics, and also it can give you excellent membership concealment. In such a case a new anonymity risk is introduced, an attacker can try to follow you by your wireless adapter and connection patterns. One potential risk is the fact that in a persistent setup you will have a fingerprint that identifies your sessions as belonging to one entity in the form of the three Tor entry guards you use. Tails used without persistence can counter this as every session will give you three new entry guards, however by not having persistence you have weakened the anonymity Tor can provide substantially. Additionally you can be geospatially tracked by your MAC address unless you spoof it, and even by the forensic artifacts that the vibrating elements in your WiFi adapter introduces to your wireless data flow. Now being geospatially trackable may not be totally bad if the attacker can not link your illegal activity to that wireless adapter in the first place (ie: Tor still offers you anonymity), but it does bring up the issue of being trackable in the same way that (but to a lesser than) someone can be tracked while carrying a cellphone. However it gives the huge benefit that even after you are traced through Tor, you still have some degree of anonymity, particularly since now your attacker will need to use pretty sophisticated measures to completely narrow in on you at this point, provided that you select random WiFi access points. Selecting WiFi access points in a pattern from a small set of possible locations is a technique that has been defeated by the feds on numerous occasions. On the other hand, a Desktop can not use WiFi from random and rapidly changing locations. The best a Desktop user can do is use a neighbors WiFi, and even if they use powerful antennas to get connections from further distance, once they are traced through Tor their attacker merely needs to do a wireless trace back to their fixed location. This is still an improvement to anonymity, it can provide you with perfect unlinkability so long as you quit using hotspots from that location prior to the feds breaking your Tor circuit and getting near your geospatial location with directional antennas. This is nice, as normally if you use Tor and your own internet connection, you would still need to worry about being traced even after you quit using that location to engage in communications indicative of involvement in illegal activity. However, it is not a defense that provides any protection at all until you stop using WiFi from that location for illegal activities, where as with a laptop it can be made to provide strong defense as you are constantly changing location.