Tonight on PBS News Weekend, millions turn out in what organizers call an historic flood of nationwide protests to push back against President Trump and his administration's policies.

Then a little-known company that helped create China's infamous internet firewall is quietly

selling the system to other countries around the world.

And a new book from a former CDC director offers an insider's formula for defeating the

world's worst diseases and winning the battle for good health.

Nobody's going to slap sunblock on you or move your legs to exercise. There are certain things that you need to do yourself. But we as a society can do things that will allow each of us to live longer, healthier lives and as a country to be healthier. Good evening. I'm Ali Rogan. John Yang is away. Millions turned out across the country

today for a coordinated day of protest against President Donald Trump and his administration's policies.

Organizers expected more than 2,600 no-kings rallies in big cities and small towns across all 50 states and some European capitals, including Paris, London, Madrid, and Berlin.

A similar event in June brought out more than 5 million

demonstrators across the country, but this time,

organizers said the mobilization was even bigger.

Today's protests spanned the nation and other parts of the globe.

Massive crowds turned out in major cities,

including New York, Washington, D.C., Boston, and Chicago.

Demonstrators also gathered in tiny towns,

like this one in rural Virginia and across the country.

They all shared a singular message.

Simple words, no kings.

We want to show our support for democracy and for fighting what is right.

Protesters named immigration raids and President Donald Trump's deployment of the National Guard to certain cities among the reasons they came out.

He should not be able to conduct these overreaches of his power, invading cities.

As an immigrant here in Germany, it's really important to me that America was founded on immigrants by immigrants and the fact

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