In a 5- to 6-quart pan, bring 3 quarts of salted water to a boil over high heat. Add noodles; cook according to package directions. Add peas to pasta and cook until peas are bright green and tender to bite, about 1 minute. Drain noodles and peas; then return to pan. Blend in tuna.
While noodles cook, in a 12- to 14-inch frying pan, melt butter over medium-high heat. Add flour and whisk vigorously until a smooth paste forms; stir mixture until it simmers, about 1 minute. In a bowl, mix together broth and milk. Very gradually, add this mixture in small batches to frying pan, whisking vigorously after each addition until smooth. Add wine and cook until sauce simmers and thickens, about 2 minutes.
Pour sauce over tuna-noodle mixture and gently stir to mix well. Serve immediately.