Why did Hitler want to unite Germany and Austria?

Germany wanted to Unite Austria and Germany because Hitler was an Austrian and there were 8 million German speakers in Austria, It would mean if they reunited with Austria, more living space, which was one of Hitlers main political aims. It also meant that again they would be breaking the treaty of Versailles and Pushing Britain and France even more to their limits. As well as this It would mean that those 8 million German speakers would probably want to Join Germany , more people in Hitlers army, causing a greater threat of war.