Phone SIM Card Question for travelling abroad

I am traveling to the US and my carrier is T-Mobile here in Europe.
My device (SGS4) is unlocked and plus, I encrypted my entire device.
Now when there in the US, I can just go into a T-Mobile shop and ask for a US SIM card with a US number on it.

My question would be, since my phone is encrypted, will this have any effect the way the US SIM card will operate or even function at all?

If I am in the wrong section to ask this, please re-direct me to the appropriate forum section.