If your entering the USA for any reason create a work account now. Import work ready emails going back years so it looks used. A few emails a week for a few years so sort by date looks good.
If its social media, add your company coworkers that can be seen on any front page, homepage or have some publicity surrounding them.
Thats your new travel web 2.0 social media.
If asked for any other accounts say your company policy only allows the work accounts and they can be fully accessed.
Compliance will allow all names and contacts to be cloned during the inspection and that is all the US gov will want.
Make sure your laptop is 100% new, new storage media, new OS, new work applications only, some work needed for that trip and the web 2.0, email accounts, ensure no wireless devices.
The MAC and any other unique hardware numbers will also be collected. Try to use wired networks, VPN via a new router to cover the laptops ethernet.
Do not store anything related to the VPN use.
If you can only use wifi, buy a new cheap card or device in the USA for that trip only.
Return home with the same laptop and expect another inspection, deep media scan, to show accounts, clone of all data, have a few new work related emails to show, a search for any encrypted partitions ect.
Really its just the same security any traveller would take when entering any nation with a digital domestic collect it all policy.
Be aware of any offers of fews wifi, hotel wifi, cafe wifi near hotel. SIM cards are also a huge risk.
"New Snowden docs show Canadian spies tracked thousands of travellers"
"SIM card makers hacked by NSA and GCHQ leaving cell networks wide open"