1. A radiographic image generation device comprising: a radiographic image obtaining unit for obtaining radiographic images for different imaging directions taken by applying radiation to a subject from the different imaging directions; a tomographic image generation unit for generating a plurality of first tomographic images having a first slice thickness based on the plurality of radiographic images obtained by the radiographic image obtaining unit and generating a plurality of second tomographic images having a second slice thickness that is greater than the first slice thickness based on the radiographic images; a MinIP processing unit for applying MinIP processing to the first tomographic images to generate a MinIP image; a MIP processing unit for applying MIP processing to the second tomographic images to generate a MIP image; and a composite image generation unit for performing combining processing using the MinIP image and the MIP image to generate a composite image.