Countries impacted by President Trump's tariffs are punching back strategically.

The European Union announced tariffs on $28 billion worth of goods from the U.S., including poultry, bourbon and motorcycles.

"The European Union must act to protect consumers and business," European Commission President Ursula von der Leyen explained on Wednesday. "The countermeasures we take today are strong but proportionate."

The EU tariffs will go into effect in two steps, starting on April 1. They'll be fully imposed on April 13.

Some of the items on the list are intentionally aimed at targeting Republican-leaning states, according to Dr. Albert Williams, a professor of finance and economics at Nova Southeastern University.

"They're saying that if you hit us and some of the things coming over, we're going to hit you where it hurts," Williams said. "That's the thinking they have in mind right now."

China also imposed retaliatory tariffs this week, hitting U.S.-produced chicken, pork, beef and soybeans.

The measures take aim at U.S. farmers, a group who overwhelmingly supported President Trump in the last election.

"(Countries) are saying we are going to hit products that come from states where they urgently need to export," Williams said. "For example, beef and even soybeans and corn are produced by our farmers, and the farmers are generally supporters of our president, and therefore, if they hurt, they will cry foul and they will definitely send into their politicians: 'This is not working. We need some changes.'"

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Right now, the countries involved are digging in. President Trump threatened a 200% tariff on alcohol from Europe after the EU announced its new tariffs.

Williams says the solution isn't continued tit-for-tat tariffs.

"This doesn't lead to a very easy solution," Williams said. "Solutions will only come when countries negotiate at this point in time."

Measles cases have now been reported in 13 states this year, after Maryland's Department of Health confirmed a case on Sunday in a Maryland resident who traveled internationally.

Measles is an infectious disease that can be serious, particularly among young children.

"Measles is one of the most contagious infectious diseases among humans," virologist and Johns Hopkins University professor Andrew Pekosz said. "If you're in the room with someone infected with measles, there's a 95% chance that you'll be exposed to the virus and potentially infected if you're not vaccinated."

The Centers for Disease Control and Prevention had confirmed 222 cases of measles in the U.S. as of March 6. A third of those cases were in children under the age of five years old.

Two deaths have been connected to measles this year, both in individuals who were unvaccinated.

"If you're vaccinated against measles, you really have very little concern with the current outbreaks of measles going on," Pekosz said. "But if you're unvaccinated, you're highly susceptible to infection."

The rising number of measles cases is taking place amid increased vaccine skepticism. A poll from KFF found 82% of parents of children under the age of 18 say they normally keep their child up to data with recommended vaccines. That's down eight percentage points from 2023.

Meanwhile, the Trump administration has made cuts to public health agencies and is now offering a $25,000 buyout to most employees at the Health and Human Services Department. Those buyouts would include staff at the Centers for Disease Control and Prevention, the National Institutes of Health as well as the Food and Drug Administration.

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Pekosz is among the health experts who worries about the impact of these cuts.

"I think the real effect of cuts at NIH and CDC is the lack of communication about the measles vaccine and its effectiveness," Pekosz said. "HHS performs a lot of functions that help maintain the health and safety of the U.S. population. Mass layoffs, people leaving the agency, are all going to affect the ability of that agency to maintain its ability to respond and maintain the health of the population."

There are new questions concerning air safety, following the mid-air collision between an American Airlines flight and a military helicopter on Wednesday.

According to an FAA report, one air traffic controller was coordinating helicopter traffic and plane traffic at the time of the collision.

But former FAA Administrator Randy Babbitt told Scripps News that's not out of the ordinary, given the time of night.

"At noon at (Reagan) National Airport, it's very, very busy," Babbitt said. "There's a lot of helicopter traffic. So, you have somebody devoted purely to coordinating the integration of helicopters into that airspace to work with the people who are controlling the aircraft within that same airspace. At 10:00 at night, this one helicopter, you don't need a fully assigned person. ... To have an airplane and a helicopter with the same person is just not that big a deal."

But long before this incident, concerns existed about air traffic control staffing.

From 2011 to 2023, the number of certified professional air traffic controllers declined by 9%, according to the National Air Traffic Controllers Association, the union representing air traffic controllers.

An FAA report from 2023 notes the 2019 government shutdown "resulted in large hiring and training delays" and says on-the-job training was "significantly reduced" because of the pandemic. A separate report from that year found 77% of critical facilities are staffed below the FAA's threshold.

But the FAA also stressed that its current levels are safe and says it would reduce air traffic before compromising safety in any way.

"The supposed understaffing of the tower is not a true consideration of causation at this point," aviation expert Steve Cowell said.

RELATED STORY | FAA implements helicopter restrictions near Reagan National Airport after deadly collision

Babbitt agrees given what he's learned about the collision so far.

"From what I have heard, it sounds to me like the controller did exactly what he was supposed to do," Babbitt said.

President Trump and Transportation Secretary Sean Duffy both stressed on Thursday that flying remains safe.

Babbitt agrees and emphasized the strong work of air traffic controllers.

"The public should have confidence in this air traffic control system," Babbitt said. "I don't think the system's unsafe at all. I think it's by far the safest system to move people."