Medicare fraud is conservatively in the $16 billion+ per year range[1] and a lot of it is easily detectable with data the government already has.

Two things about this type of fraud though:

1. Detection would require making USG a better place to work for technically savvy people, with things like "budgets" and "not getting publicly humiliated by the world's richest man"

2. It's committed by men in suits, so enforcement would require going after the types of people that in reality, Trump & co prefer to pardon... for committing exactly this type of fraud [2]...

So, cutting life-saving aid, cancer research, and healthcare benefits it is!

[1]: https://www.wsj.com/health/healthcare/how-health-insurers-ra...

[2]: https://www.nbcnews.com/politics/politics-news/health-care-f...