What will he think when La Marseillaise is played on Tuesday in the St Petersburg stadium before a World Cup semifinal?
How will he feel standing there in front of the Belgian bench, just a few metres away from the French one?
For the first time in hislife, Thierry Henry will want France to lose. One of the most legendary players the country has ever known, a World Cup and European winner with Les Bleus, the greatest goalscorer the national team has ever seen (51 goals in 123 caps), a former captain and an icon for a lot of French kids growing up.
On Tuesday, he will represent the enemy.
For the last two years, Henry has been the assistant of Roberto Martinez, the Belgium head coach, specially chosen to mentor the Red Devils' forwards. To see him wearing the Belgian's training kit is weird. To think that he will wish France to lose is even weirder.
"Yes, it is weird, because he is French and that he will be on the bench of the opposition," Didier Deschamps said on Sunday morning on French television. "For him as well, it will feel weird."
Olivier Giroud shares the same opinion: "He gives his precise and important advice to the Belgians. For sure, I would rather him being with us and giving me the advice but you can't be jealous and it is not shocking me at all.
"I would be proud to show him that he picked the wrong side. It will be strange to have him against us on this game. It will be a special match for him."
On Tuesday, it will be Henry versus France and Henry versus Deschamps, his former teammate for both France and Juventus. They know each other so well. They were not part of the same generation -- Deschamps is nine years Henry's senior -- but they respected each other.
They never lost a single game playing for France together (21 matches, 16 wins, 5 draws) and won the World Cup in 1998 and the Euro in 2000. Is Henry a traitor?
"No. This is just an opportunity for him to learn the job without any pressure," says Arsene Wenger.
Henry did not choose the Belgian bench over the French one. He constantly repeats, to anyone who asks, that France never offered him a role.
"We lost touch with him, he has little contact with the French federation," Noel Le Graet, president of the French FA, told AFP on Sunday.
"That's life. He has been in England for a long time. Personally, I have little contact [with him]."
World Cup 2018 must-reads
- Make your daily ESPN FC Match Predictor picks!
- World Cup fixtures, results and coverage
- World Cup Daily live: Follow the action with ESPN
- Why has World Cup been full of surprises?
- Ronaldo, Messi finally have rivals for Ballon d'Or
- Semifinal preview: Belgium pressure, England hope
- No sleep 'till Moscow: Fan travels through Russia
Henry's story with France started like in a dream and ended in a nightmare. From 1998 and a World Cup medal on home soil at just 20 years of age to 2010 and a disgraceful team strike in South Africa that he could have stopped but didn't at 32.
The Arsenal legend felt rejected by his own country. In 2009, after his infamous handball against Ireland in the 2010 World Cup playoffs, Henry never felt supported by his people either. He has always needed to feel loved, and feels that he was never given the farewell he feels he deserved at the end of a career where he gave a lot to France. The love story turned sour.
Nowadays, Henry probably feels more English than French after living most of the last 20 years in London. He must have an affinity for Belgium, maybe an allegiance to them as well. But he is still French and still means a great deal to French football.
One would also think that French football still means a lot to him too -- maybe not so much on Tuesday however.