But to answer the question Europeans are asking - here in the US we have a strong executive directly elected president. Every country that has this system has this problem.
Even worse, we have an insurmountable 2/3rds requirement for removal in the senate, a body tied to state, not population. We've impeached and removed many politicians but never a president.
The Andrew Johnson impeachment pretty much proved that it's impossible. It's simply not analogous to what's possible in parliament.