This bill wants to make a program, called "Securing the Cities," work better by picking the best places to join based on how prepared they are for dangers, like big scary attacks. It also wants to see how well the program is going and tell the grown-ups in charge in two years what they find out.

The Senate has written a letter saying it's important to keep promises about not making too many big bombs, and they're upset because Russia is stopping one of these important promises. They also want countries to talk more about how to be safe with these big bombs so everyone can feel safer.