 Kọ itẹsiwaju fun paragirafi yii - O nṣakoso Ẹgbẹ Ẹgbẹ Tank 326th, Brett, ti o jẹ ọga agba ni bayi, ṣe itọsọna ikọlu ọkọ ayọkẹlẹ Amẹrika akọkọ ti Ogun Agbaye akọkọ ni Ogun ti Saint-Mihiel ni Oṣu Kẹsan ọdun 1918 ati, lẹhin ti ọgagun George S. Patton farapa, gba aṣẹ ti Brigade Tank 1st ni isansa rẹ. Brett gba àmì ẹyẹ Distinguished Service Cross fún ipa tó kó nínú ogun náà. Kò pẹ lẹyìn náà ni Ogun Àgbáyé Kìíní parí, ní November 11, 1918 : ó ṣe tán. Ni afikun si Agbelebu Iṣẹ Aṣayan, awọn ohun ọṣọ miiran rẹ lati ogun naa ni: Silver Star pẹlu Oak Leaf Cluster, Purple Heart pẹlu awọn ẹgbẹ Oak Leaf meji, Croix de guerre Faranse 19141918 pẹlu ọpẹ ati Oṣiṣẹ ti Legion of Honour. 