To state the obvious, the Trump administration is more interested in profiting from a minerals deal than supplying any actual security guarantees. The Russian Federation has proved time and time again that they will breach any peace agreements (as occurred with the current invasion which breached agreements bartered after the annexation of Crimea) made with Ukraine for piecewise annexation of their neighbors, at any price to their own soldiers and people.
True lasting peace, is avoiding further steps to another world war. It takes hardly a high school education in history to recognize those preliminary warning signs in Russia's behavior. A common talking point that the Trump administration seems to use, is that they are doing precisely that- preventing a world war- by refusing to further arm and protect Ukraine with weapons and security guarantees- however this refusal does just the opposite, and this minerals deal really has nothing to do with Ukraine's security or interests. The devil is in the details, and the Trump admin refuses to detail how the minerals deal would protect Ukraine or how they would respond to further territorial incursions if the deal were to be signed.
Aside from all this, of course there's a lot of topical nonsense in how Trump and Vance conducted themselves, with shouting and lecturing at Zelensky, but these are all distractions, and they have almost no substance or details to back their broad claims about how or why this conflict started and what would end it. Scapegoating and bullshitting seems to be their game, but luckily Zelensky both asserted himself where possible and kept a relatively calm, but brutally honest, demeanor.
Because the security threats to America would come a bit later, likely in the form of Russia marching into a NATO country, Americans will believe what they want about the conflict. Trump makes this especially easy with his false and misleading oversimplifications. It is sad to think that a proportionally small sacrifice by the American taxpayer to help a country like Ukraine has been sized up as unworthy collateral for saving lives and fighting fascism.