The proposed cuts in spending by the Trump administration are causing significant concern for the National Science Foundation (NSF), with potential repercussions for the development and deployment of the upcoming "Horizon" supercomputer at the Texas Advanced Computing Center (TACC) at the University of Texas. The Horizon machine, set to be the most powerful NSF-funded supercomputer ever built, is now at risk due to a budget dispute between Congress and the White House over what constitutes emergency spending. In March, Congress allocated $234 million to the NSF's Major Research Equipment and Facilities Construction (MREFC) budget, part of the larger $9 billion NSF budget for fiscal year 2025. This funding was primarily intended for the ongoing construction of Horizon, which is scheduled to launch in early 2026. However, President Trump decided to veto $2.9 billion in emergency spending, including the $234 million allocated to the NSF. Over half of the NSF funding, $154 million, was specifically earmarked for the Horizon project. This move has sparked a heated debate over the definition of emergency spending and whether the President has the authority to override Congress's decisions in this regard. The details of the Horizon supercomputer are still emerging, but TACC has provided some preliminary specifications. The system is expected to achieve a peak theoretical performance of 400 petaflops on 64-bit floating-point math, representing a tenfold improvement over the current Frontera system, which boasts 38.75 petaflops at FP64 precision and cost $60 million. For artificial intelligence (AI) applications, which typically require lower precision math, Horizon will be approximately 100 times more powerful than Frontera. To bridge the gap between Frontera and Horizon, TACC unveiled an interim machine called "Vista" in September 2024. Vista is a collaboration between TACC, Nvidia, and Dell, utilizing a mix of compute nodes equipped with Nvidia's "Grace" CG100 Arm CPUs and "Hopper" GH100 GPUs. Specifically, Vista comprises 600 nodes with Grace-Hopper configurations and 256 nodes with Grace-Grace configurations. The Hopper GPUs provide 20.4 petaflops of FP64 performance on vector cores and 40.8 petaflops on tensor cores, while the 512 CPUs in the Grace-Grace nodes contribute 1.8 petaflops of FP64 performance. Together, the 600 Grace CPUs in the Grace-Hopper nodes add another 2.3 petaflops, resulting in a total aggregate FP64 compute power of 44.9 petaflops for the Vista system. Given the technological trends and the choice of Nvidia components for Vista, it is reasonable to speculate that Horizon will adopt a similar architecture, incorporating the next-generation "Vera" CPU with 88 cores and the "Rubin" GR100 GPU. The total budget for Horizon, established in July 2024, is $457 million, covering the machine's cost as well as operational and facilities expenses. However, the exact breakdown of this budget remains unclear. The delay in funding for Horizon could have severe consequences. Not only does it jeopardize the timeline for the machine's completion, but it also risks TACC's position in the queue for receiving Nvidia GPUs, which are critical for high-performance computing (HPC) and AI research. Many scientific and academic projects are depending on Horizon's superior capabilities to advance their research, particularly in fields that require extensive computational resources. Industry insiders are closely monitoring the situation, emphasizing the importance of maintaining federal support for scientific research and HPC systems. The American Association for the Advancement of Sciences (AAAS), a leading scientific organization, has voiced concern over the potential impact of these budget cuts on innovation and discovery. They argue that the NSF's role in advancing HPC and AI technologies is crucial, especially as these fields continue to grow in significance and application. The Texas Advanced Computing Center, known for its cutting-edge research and supercomputing capabilities, is a vital institution in the HPC community. TACC's Horizon supercomputer is poised to play a pivotal role in pushing the boundaries of scientific computing and facilitating groundbreaking research. It is imperative that the federal government recognize the strategic importance of this investment and resolve the funding dispute promptly to ensure the continued progress and leadership in HPC and AI technologies.