Step 1: Cook the chopped bacon in a large pot over medium heat until crispy, about 5 to 7 minutes. Transfer the bacon to a large bowl using a slotted spoon.
Step 2: Reduce the heat to low and stir the butter into the bacon grease until melted. Add the lobster and cook until firm, about 4 to 6 minutes. Transfer the lobster to the bowl with the bacon using a slotted spoon.
Step 3: Bring the water in the pot to a boil and cook the pasta according to package instructions.
Step 4: In the bowl with the lobster mixture, add the celery, onion, tomatoes, mayonnaise, lemon juice, garlic, tarragon, salt, and pepper. Stir until well combined.
Step 5: Drain the pasta and let it cool slightly. Add the pasta to the bowl and toss to combine.
Step 6: Serve the pasta salad warm, or chill it in the refrigerator for 2 hours before serving.