U.S.-Mexico economic interdependence through the USMCA trade framework, combined with ongoing bilateral security cooperation on fentanyl trafficking and border management, underpins trader consensus against a full-scale U.S. invasion in 2026. Mexican President Claudia Sheinbaum has repeatedly and publicly rejected any U.S. military presence on Mexican soil as a violation of sovereignty, a stance reinforced by domestic political opposition and historical precedent. Recent U.S. actions remain limited to intelligence alerts, cartel designations as terrorist organizations, and pressure for joint operations rather than unilateral ground forces, with congressional proposals like an Authorization for Use of Military Force facing significant resistance. Even amid tensions over drug enforcement, the absence of troop mobilizations or formal war declarations sustains the 97 percent implied probability on "No." Late-year shifts could arise only from extreme, unforeseen escalations such as direct attacks on U.S. interests originating from Mexican territory, though these would more likely prompt targeted measures than broad invasion.