The Flemish Greens’ young gun Kristof Calvo, in the federal parliament | DIRK WAEM/AFP/Getty 5 ways to fix Belgium, from a Green boy wonder Kristof Calvo is young, ambitious, and wants to make his divided country whole again.

A 28-year-old Green politician with a new book called "F*ck the sideline" challenges Belgium's center-right government — and the Flemish nationalists who are part of it — with disarmingly simple solutions to the country's byzantine problems.

Kristof Calvo, the Flemish Greens' boy wonder and leader in the federal parliament, is one of the most vocal critics of Liberal Prime Minister Charles Michel's government.

The book, which he is promoting in conference halls, community centers and television shows across Belgium, is a leftist manifesto for a country that has taken a turn to the right. It has been flatteringly compared to the "Citizen Manifestos" that enabled Liberal leader Guy Verhofstadt to revitalize the Belgian political debate in the 1990s and helped propel him to prime minister from 1999-2008.

In the chapter "Long Live Belgium," Calvo takes on the political hot potato that has been a vote-loser for the left in recent years: Belgium's struggle with its Flemish-nationalist movement.

Here are five of Calvo's most eye-catching ideas for overcoming divisions between Dutch and French speakers to make his country whole again.

1. Nationalists: Put up or shut up

Scotland and Catalonia have sought referendums to test their aspirations for independence, but not Belgium's Flemish-nationalists. Calvo challenges them to have the courage of their convictions.

"If [the New Flemish Alliance, part of Michel's coalition] wants to campaign on this issue, they have to have the conviction to do what Scots and Catalans did. They have to have the courage," he said in an interview. "The debate on Belgium is in need of some clarity. The silent majority that isn't nationalist deserves to be heard."

A referendum on independence for Flanders looks doomed to be a non-starter. Political scientists estimate that only one in 10 Flemish people would support a split from Wallonia and polls suggest people increasingly identify themselves as Belgians more than Flemish.

One member of the New Flemish Alliance recalled Belgium's only previous referendum, in 1950, which led to rioting and deaths. It is “not exactly worth repeating,” said Hendrik Vuye, the party's parliament leader.

2. Language: Let's try English

Belgium claims three official languages: Dutch, French and German. Calvo argues, counterintuitively, that it could use one more.

"We have to move away from the rigid approach to a functional approach on public administration," Calvo said. "Where possible, the government could serve its citizens in Dutch, French and English — we can launch experiments on this."

Language is a particularly sensitive issue in Belgium. The Flemish and French-speaking regional governments insist on exclusive use of their first languages and in some areas, public officials are forbidden by law from using the other language.

3. Internal borders: Students must mingle

Europe's flagship exchange program Erasmus connects students across national borders. Belgium would benefit from the same approach to overcome its internal cultural and linguistic divide, Calvo argues. Further still: It should be mandatory.

"The idea of an ‘Erasmus.be’ consists of sending high school students to the other part of the country for some weeks, as an obligatory exchange program," he said.

In fact, the country already has such a program for university students, though it is optional. Students from Liège can spend part of their "European" exchange program in Antwerp. Students from Louvain can choose Louvain-la-Neuve.

4. Lost in translation: Let's try subtitles

Resistance to learning the other national language is a thorny issue in Belgium. Flemish politicians constantly complain that French-speaking schools don't offer Dutch as a mandatory subject, whereas Flemish children all study French.

Calvo has a simple solution involving Belgium's public broadcasting, which is also divided along linguistic lines. French-language RTBF and Dutch-language VRT are housed in the same building but, beyond informal exchanges and the odd collaboration on a program or news story, they mostly live separate lives.

Employees refer to the corridor that divides the two services as the "language border."

"Subtitles would make it more accessible to watch each other's media coverage" — Kristof Calvo

Calvo's proposal: "Subtitles would make it more accessible to watch each other's media coverage. It's also a practical way of stimulating multilingualism."

One public television talk show already gave it a test-drive when Calvo did an appearance.

5. Here's a thought: national elections

This idea may not sound radical in other places in the world, but most Belgians (outside Brussels) can vote only for politicians from their own region — Dutch-speaking Flanders or French-speaking Wallonia — to represent them in parliament. This means there is no such thing as a national politician and there is very little crossover in the public debate.

"In fact, it's the one idea that would trigger an automatic change of many of the other issues I discussed in the book," the young Green said. "For one, you'd have more Flemish politicians on French-speaking talk shows, and more French-speaking politicians on Flemish TV.”