 One event on the president's schedule for this week, the NATO summit in Washington. ABC's Perry Russom has a preview. At the summit, the U.S. is expected to announce new steps to strengthen Ukraine's air defenses and military capabilities. And there will be significant announcements on increasing NATO's military, political and financial support for Ukraine. On the sidelines of the summit, President Biden will host an event with Ukraine's President Volodymyr Zelensky, along with other NATO leaders.