The tax that Valve is referring to in ordering the packages is the sales taxes that Valve has to collect for certain states domestically in the United States - not all of the states in the US will be subject to this tax.
For internrational customers, you will not be subject to this tax at all as it's for domestic United States sales only.
For internrational customers, you will not be subject to this tax at all as it's for domestic United States sales only.