[jandrese]

GPS jamming defense in the US is mostly provided by the FCC bringing the hammer of God down on people who run GPS jammers. The penalties for interfering with navigation signals are severe.

[mmh0000]

HAMMER OF GOD[1][2][3][4][5]

[1] https://www.fcc.gov/general/jammer-enforcement

[2] https://www.fcc.gov/document/fcc-fines-florida-driver-48k-ja...

[3] https://www.cnet.com/culture/truck-driver-has-gps-jammer-acc...

[4] https://www.fcc.gov/document/fcc-upholds-fine-jammer-used-bl...

[5] https://docs.fcc.gov/public/attachments/DOC-339560A1.pdf