Bilateral trade, even peace-promoting trade, is not without observable externalities that harm other states, yet most of the trade-conflict literature has ignored these concerns. Some of these externalities arise when domestic exporters compete with exporters from foreign nations for markets in other countries, and I hypothesize that leaders react to this competition in venues beyond the trade negotiating table which can even include the battleground. Specifically, I argue that countries find themselves in competition with not only the countries that export similar goods to the world but also and especially those countries that export to similar markets. Analyzing robust data on bilateral commodity-level trade and militarized interstate disputes, my analysis shows that countries which share more similar portfolios of export destinations for their goods are more likely to come into conflict and that varying this export destination similarity score raises the likelihood of conflict substantially.