When the Senate Appropriations subcommittee on defense released a summary of their spending priorities June 26, the bill included a significant increase for one emerging technology.

The panel recommended setting aside an additional $447 million for microelectronics. Specifically, the committee wanted to ensure the Department of Defense has access to trusted microelectronics and can develop manufacturing processes for next-generation microprocessor chips. To do so, the bill raised the fiscal year 2019 research, development, testing and evaluation budget for microelectronic technology from $169 million in the president’s fiscal year 2019 budget request to $616 million.

Already, concern about the domestic production of microelectronics is expected to be part of a large defense industrial base review now underway.

But what exactly are microelectronics, and why is their development worth so much to DoD?

Microelectronic chips are essentially integrated electric circuits that regulate energy consumption, and perform complex computations that enable capabilities like global positioning systems, radar and command and control. Imagine all of the components that go into your computer ― memory, graphics processors, wifi modules, etc ― all on a single silicon chip, called a wafer.

Leading-edge wafers typically are 300 mm in diameter and loaded with transistors, resistors, insulators and conductors that control the flow of electrons (read electrical energy) across the chip. The smaller and smaller these components are, specifically transistors, the more can be fit on a chip, enabling faster and more efficient processing.

Transistors themselves are measured in nanometers (nm), and are unfathomably small to most non-scientists and engineers. One nanometer equates to a billionth of meter! To put that into perspective, the average diameter of a human hair is 75,000 nm.

The most cutting-edge transistors used in microelectronics measure between 10 and 7 nm, and are expected to get smaller in coming years.

Smaller and smaller transistors will contribute to breakthroughs in “machine learning, data sorting for recognition of events, and countering electromagnetic threats,” according to a Defense Advance Research Project Agency backgrounder.

Because Pentagon leaders believe this technology is vital for current and future capabilities, technology officials say it is important DoD can trust microelectronics are reliable and secure from adversary attacks and sabotage.

For this reason, DARPA launched the five-year Electronics Resurgence Initiative in September 2017 “to nurture research in advanced new materials, circuit design tools, and system architectures.” In FY18 the program was allocated $75 million. In the FY19 President’s budget ERI funding included annual investments of $300 million over the next five-years, potentially upwards of $1.5 billion over the initiatives lifetime.

A key thrust of this initiative is partnership with top universities through the Joint University Microelectronics Program, or JUMP. The program enlists top researchers to work on proejcts like cognitive computing, secure cellular infrastructure to support autonomous vehicles and intelligent highways and other technologies enabled by microelectronics.

Under the Senate defense subcommittee’s markup, ERI received an additional $30 million to help “reestablish U.S. primacy in assured microelectronics technology.”

Correction: an earlier version of this story contained incorrect budget figures from DARPA