Sam, on the contrary derech eretz kadma laTora. The Netziv, in his introduction to Sefer Breisheet says that it is called “Sefer HaYashar” because the Avot even acted civilly to lowly idol worshippers – this laid the groundwork for Matan Tora. When Rav Yisrael Salanter’s granddaughter was looking for a shidduch he told her to first see if he is a mentsch. If he is also an ilui that is a bonus.
In the sense of work, there is a Chatam Sofer on Sukka 36a (which was censored by the anti-Zionists) that any work one does is a kiyum of the mitzva of building the Land. Even in Chutz laAretz, if there is no flour there is no Tora and if there is no Tora there is no flour. Similarly, if Yoav had not made war david could not have made justice (Tora) and vice-versa (Sanhedrin 49a). The point is taht there is a symbiotic relationship between Tora and Derech Eretz. Rav Asher Weiss asks how Yissachar could sell half of his reward for talmud Tora. He answers that by enabling Yissachar to learn half of the mitzva was Zevulun’s by right. Similarly, a bachur once came to the Chazon Ish and told him that his kalla was willing to support him on condition that she received half the reward for his learning (she wanted to put it in hte ketuba). The Chazon Ish told him that in that case she would get three-quarters.