1. Young voters came out in droves in 2022 to crush the "red wave". If Vivek wanted to raise the age they would swamp the GOP again.
2. Ukraine was given security guarantees by the US if they gave up their nukes.
en.wikipedia.org
The memoranda, signed in Patria Hall at the
Budapest Convention Center with US Ambassador
Donald M. Blinken amongst others in attendance, prohibited the Russian Federation, the United Kingdom and the United States from threatening or using military force or economic coercion against Ukraine, Belarus, and Kazakhstan, "except in self-defence or otherwise in accordance with the
Charter of the United Nations." As a result of other agreements and the memorandum, between 1993 and 1996, Belarus, Kazakhstan and Ukraine gave up their nuclear weapons.