thesis help., i need help with a US history thesis for a DBQ Options

[smashedcodes]

I have to do a DBQ (document based Question)

and I always have trouble with coming up with a thesis.
either I have no thesis or it isn't stated right.

I just wanted some input to see if I have a proper thesis and if not
some suggestions on how i can improve it.

The question is...

It was the strength of the opposition forces, both liberal and conservative, rather than the ineptitude and stubbornness of President Wilson that led to the Senate defeat of the Treaty of Versailles.

Using the documents and your knowledge of the period 1917-1921, assess the vailidity of this statement.

Ok and my thesis (or attempt at thesis) is..

Wilson's own stubborness and ineptitude led to the senate defeat of the Treaty of Versailles. Most of the senate just wanted to make some revisions to the treaty. Wilson's stubborness didn't allow the revisions to be made and the treaty went unsigned.