European leaders called on Friday for greater unity in developing the continent’s security and defence capacities as former US president Donald Trump’s potential return to the White House rattles Washington’s EU and NATO allies. Trump’s shadow loomed large on the first day of the 60th edition of the Munich Security Conference, an annual gathering in the southern German city of top political and defence officials to debate international security policy. The main topics on the three-day conference’s agenda are the ongoing conflicts in the Gaza Strip and Ukraine. Russia was firmly in the spotligh…