One of my favourite films is the 1993 Stalingrad for it's sheer and brute representation of war in Eastern Europe between the Russian and German soldiers. In a specific scene, there is a Christian (not sure if Lutheran or Catholic, but probably Lutheran) minister preaching to the German soldiers after they finish singing a Church tune of some sort. The preacher, with the Bible in his hands, goes on to preach to the German soldiers that they're superior to the Soviets as the Soviets do not have God with them, and that they're godless evil creatures.
"Gott mit uns" was featured on some regimental WW2 German belt buckles as they historically have featured this phrase. If the Nazi German state was irreligious, than why was this a featured part of the Wermacht uniform?
Was the Nazi ideological state truly anti-religious? Was personal religion with Catholicism or Lutheranism (or others) allowed?
Gott mit uns goes way, way back in German history. Its use as a slogan was to connect the Wehrmacht to the long tradition of German (and before that, Prussian) success at arms.
As to the degree of Nazi persecution of religion, it was uneven. While the government did interfere with the functioning of the Catholic and Protestant Churches, and Hitler and other senior Nazis often made quite a few anti-christian speeches, they also made quite a few pro-christian speeches. Even at the height of anti-Catholicism, Catholic religious practice went uninterrupted - it was only when Catholics tried to bring their religion into the political arena that they were persecuted (and they were quite vigorously persecuted, admittedly). But to simply practice Catholicism privately, owning a bible, praying, attending services etc, wasn't forbidden or even especially frowned upon. It might have excluded one from the upper echelons of government, but it certainly didn't affect regular soldiers.
Similarly, Catholic chaplains served with the Wehrmacht, so the scene is entirely accurate.
There is debate as to whether or not the Nazis planned to eventually eradicate christianity or to keep it (presumably in a suitably chastened and conformist form). But even those who believe the Nazis' eventual goal was to eradicate Catholicism concede that it was being postponed until after the war, as it would have required resources and energy that they couldn't afford before the final victory.
According to the terms of the Reichskonkordat Catholic chaplains were provided for the soldiers in the German army. Sadly, too many of the clergy involved put more emphasis on Divini Redemptoris (the March 1937 encyclical opposing communism) than on Mit Brennender Sorge (the encyclical detailing the Vatican's problems with fascism issued in that same month).
So, while Hitler made some comments opposing Christianity and Catholicism, he also made some comments in support of religion. Largely, he was a pragmatist, and would push on the issue as far as he could and no further. With large portions of his population claiming religious affiliations, this was about the only stance he could take to reconcile his own views with the situation at the time. Allowing chaplains to minister to the troops--after a vetting process by the Gestapo--kept Catholic troops in the field.
As an aside, the 1993 Stalingrad is an incredible movie. I highly recommend it, but only for mature audiences. I last watched it in 1995, and some scenes still stick with me. It is simply brutal.
"*Hitler was"
It seems that Hitler himself was conflicted. He hated Christianity for advocating weakness yet respected Jesus for his strength.