Massive resource for diggers. As of today:

2542 videos of President Trump: https://archive.org/details/trumparchive

915 videos of Congress: https://archive.org/details/us_congress_archive

3834 videos from the Executive Branch: https://archive.org/details/executive_branch_archive

These are special collections in the Internet Archive [of] TV News; there is much more there as well:

https://archive.org/details/tv