from brussels, special correspondent ryan chilcote begins our coverage. >> reporter: jets blazed over brussels and nato's gleaming new headquarters this afternoon, the flags of all 28 member states making a show of unity. but a short time earlier, with his fellow leaders looking on, president trump renewed his longstanding demand: nato allies must do more. >> member nations are still not paying what they should be paying and what they are supposed to be paying for their defense. this is not fair to the people and taxpayers of the united states. and many of these nations owe massive amounts of money from past years and not paying in those past years. >> reporter: the president noted the bloc did however, shell out for that new home. >> i never asked once what the new nato headquarters cost. i refuse to do that. but it is beautiful. >> reporter: german chancellor angela merkel, speaking before the president, struck a different note in unveiling a memorial of the berlin wall. >> ( translated ): our alliance is united in the awareness of the importance to cooperate to insist on freedom an