NATO is a military alliance established by the North Atlantic Treaty of April 4, 1949, which constitutes a system of collective defense whereby its member states agree to mutual defense in response to an attack by any external party. Friedrich Merz is the leader of Germany's Christian Democratic Union (CDU) and is expected to become the next Chancellor. Recent comments by Donald Trump have caused Merz to question the future of NATO. - Friedrich Merz, poised to become Germany's Chancellor, has expressed doubts about NATO's future given recent US policy shifts under President Donald Trump. - Merz emphasized the need for Europe to rapidly develop its own independent defense capabilities. - Merz questioned whether NATO would remain in its current form by June. - Merz's comments come after his party's victory in the national election, where he vowed to pursue real independence for Europe from the US.