Recent Russian incursions into NATO airspace have sharpened divisions inside the alliance over how to respond, exposing both the strength and the limits of collective defense.

Axar.az reports, citing Fox news, Secretary General Mark Rutte clashed with Estonian Prime Minister Kristen Michal last week after Estonia invoked NATO’s Article 4 clause, which triggers consultations when a member feels its security is threatened.

According to three European officials granted anonymity to speak freely, Rutte argued that repeated invocations risked diluting the treaty’s force. One source said he even raised his voice at Michal, warning that NATO must be cautious about how often it signals alarm.

Rutte argued that if Article 4 were invoked every time Russia violated sovereignty — through drone incursions, fighter jets, cyberattacks and more — it would quickly lose impact, according to the officials.