The Charles de Gaulle aircraft carrier almost got immobilized back in the early 2000s due to withholding of spare parts from the USA because they were pissed we called bullshit on their Iraq WMD claims. The USA routinely uses ITAR as a pressuring tactic to stop European weapon sales to foreign countries, which is why we're actively scrubbing every last ITAR component from all of our weapon systems.
Just because we're allies doesn't mean that the other party has or will have our best interests at heart. The Americans have proven to be quite temperamental and under-handed when our strategic objectives aren't aligned with theirs.
Aren't you? In 2003 Russia, Germany and France were strongly against illegal American invasion of Iraq. The US invaded anyway, ruining the country. What have France and Germany done about that?
The fact that the US government decided to unilaterally invade Iraq anyway is not our responsibility to bear. What could France have done more, try and enact economic sanctions or wage war against the USA over this?
Everything it is doing now towards Russia.
Besides the logistical, economical and industrial challenge of supplying enough kit to even make a dent against the expeditionary forces of the USA, which were still doped sky-high on Cold War hand-me-downs, that sounds like a terrible idea.
Hussein's Iraq was not Zelensky's Ukraine and not just because of strategic reasons. The Gulf War happened because Hussein wasn't a friendly neighbor to Kuwait.
"Giving weapons and ammo to Saddam Hussein?"
The US is giving weapons to Azov [0], Ukrainian neo-Nazi ultra-nationalists.
Poland, being Poland, was after Iraqi oil [0].
France kept doing business as usual with the US despite American illegal war.
It's not that we don't trust the Americans per se (although opinions may differ on that topic), but we don't want to have to.
ArianeGroup also manufactures the M51 missile that goes inside our SSBNs and unlike the Brits we do not accept depending on Americans supplying us with the missiles for our nuclear deterrent.