Through a massive arms build up and and funding internal projects like dams and autobans and the like. Roosevelt only had the second alternative available to him.
Wpa, WPA
Don't be a fool working hard, it's passé
You'll stand for five or six hours a day.
Sit down and smoke while you joke; it's OK
WPA.
I'm so tired, I don't know what to do.
Can't get fired,
So I'll take my rest till my work is through.
WPA, WPA.
Don't mind the boss if he's cross when you're gay.
He'll get a pink slip next week, anyway.
Nobody beats this. You loaf every day.
WPA.
Skeets Tolbert & His Orchestra, Decca Records, 1940
You are making the mistake of thinking that is possible to spend our way out of depressions. Germany got out of the depression because real wages were held down. Roosevelt, by contrast, kept propping up wages and prices which equalled continued depression.