The same way there are sites tracking the ever-ballooning government debt, for example.
History.com has a fun overview (links omitted):
Is the United States currently experiencing a national emergency? No matter when you read this, the answer is “yes.”
Technically, the United States has been in a constant state of emergency since November 1979, when Jimmy Carter responded to the Iran hostage crisis by issuing an executive order declaring a national emergency and blocking Iranian government property. Even though Iran released the hostages on Ronald Reagan’s inauguration day in 1981, Reagan renewed Carter’s emergency declaration every year during his presidency. Since then, every president has continued to renew the 1979 emergency—while also declaring many emergencies of their own.
When Donald Trump started his second term on January 20, 2025, the United States had around 40 active emergency declarations (no really, we are serious), including the national emergency George W. Bush declared in response to the 9/11 terrorist attacks.
On his inauguration day, Trump initiated two more: a national energy emergency and an emergency at the U.S.-Mexican border.
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To quote Wikipedia (goto for the incomplete list):
A national emergency is a situation in which a government is empowered to perform actions not normally permitted. The 1976 National Emergencies Act implemented various legal requirements regarding emergencies declared by the President of the United States.
As of January 2025, 85 emergencies have been declared; 41 have expired and another 44 are currently in effect, each having been renewed annually by the president.
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