Hi my wife is not in the US yet and she does not have an SSN. Can I include her in my tax return?

Yes. You can choose to treat your spouse as either a U.S. resident or non-resident for tax purposes, according to the IRS. They address a Nonresident spouse here.  You do not mention any dependents, but if you have any, you could treat the spouse as a non-resident, and claim Head of Household yourself.  Or, you can file your tax return as Married Filing Jointly.  

Here are the requirements from the IRS to make the election:

"How to make the choice

Attach a statement, signed by both spouses, to your joint return for the first tax year for which the choice applies. It should contain the following information:

1. A declaration that on the last day of the tax year one spouse was neither a U.S. citizen nor a U.S. resident within the meaning of IRC section 7701(b)(1)(A) and the other spouse was, and that you choose to be treated as U.S. residents for the entire tax year.
2. The name, address, and identification number of each spouse. (If one spouse died, include the name and address of the person making the choice for the deceased spouse.)"

Please note that this signed statement means you will need to paper-file your 1040.

If you opt to file Married Filing Jointly, and your spouse has income to exclude, complete Form 2555 to exclude your spouse's foreign income. 

This article will walk you through the steps to Form 2555: What are Forms 2555 and 2555-EZ used for?