For one, your summary is based on two Secular Kingdoms Catholic Spain and Protestant England. You stated the Church of England became identified with the English Monarch. For Clarification Spain was not the Catholic church, Spain was Catholic in faith, not as the English for England along with her Protestant church joined politically, their is a fundamental difference here which I would like to clarify hopefully without derailing your point and thread.
I would say that you need to rethink this comparison.
For in Spain, France and Portugal the Catholic church was indeed joined politically to the monarchy.
In fact, in those times the Papacy had very little influence in those countries. What vexed king Henry VIII so much was that the church in England had a special subordinate arrangement with the Papacy that did not exist in some other countries. This traces back to the missions begun by Augustine to the British Isles when England did not actually yet exist, the entire territory was divided into many smaller states and the church operated across state lines with less reference to the local monarchs.
Eventually the “English” state was unified, finally, in the reign of Alfred the Great of Wessex. The church retained it’s own independence of initiative as long as possible from that time forward.
William the Conqueror asked for the Pope’s blessing to take England, and received it. This contributed to problems for him later because he found the English church not as submissive as he had expected, prompting persecution of the church to an eventual compromise.
King Henry II received a franchise to take over Ireland through a Papal Bull from Pope Adrian IV (The only English Pope). The alleged reason was to make the Irish church conform to Papal discipline. This seems to have made a lot of sense to Pope Adrian, he gave the go-ahead.
Heny II’s son, king John (there apparently was only one king John) tried to take control of the appointment of the Archbishop of Canterbury (senior bishop of the English and Irish churches) away from the local synod. This would have been in line with the authority of other monarchs of the day. The bishop of Rome was able to capitalize on the dispute by rejecting both candidates and naming his own (Stephen Langton). This frustrated both the local synod and the monarchy while enhancing Papal authority over the English church.
Others may recall this episode sparked a whole string of consequences. First John’s adamant refusal of Langton as the head of the English church, then the interdict (a major catastrophe all around) and eventually John’s excommunication, followed at a later date with his submission to Rome.
The terms of this agreement made the entire kingdom a vassal of the Papacy. (This is a matter of historical record).
Interesting sidenote: Later, when king John signed the Magna Carta, the Pope disapproved. It was this condition as vassal which enabled John to break the Magna Carta agreement, with the Pope’s support.
In summary, the weaker position of the kings of England with relation to the Pope over the English church was due to the accumulated effect of all of these different conflicts and compromises over time. The situation of the English church at the time frustrated every English monarch who could see how the Spanish, Portuguese and French churches were so much more accommodating to their kings and less subject to Papal oversight. It was a source of great resentment, which led to consequences we all are generally familiar with.