The EU isn't a womb. It is a huge market for goods and services. The UK proposes to address this market as a third party without any of the advantages that the US or China bring to the table - comparing the UK's ability to trade internationally with that of either of those behemoths is ludicrous. Furthermore, it proposes to trade with this market potentially without any of the advantages in terms of preferred access that it previously enjoyed.
Without the EU Ireland would not survive, economically, and Irish voters are not insane enough to support a proposal that would cut them off from the market where 50% of exports are sold. Additionally, without the EU there would not have been peace in NI for the last two decades, and Irish voters are painfully conscious of the potential blow to peace (the GFA) that Brexit represents.
the Common Market 1970's when there were 6 members, and is currently going in an entirely different Federal direction
Au contraire, the hope of closer political union was always known. It was not a secret, or a development out of the blue, or a bait and switch. In the late 50s and early 1960s when Ireland sought to get its act together to present an acceptable application for membership, one of the sticking points was Irish neutrality. The Taoiseach of the time, Sean Lemass, had to bend over backwards to reassure the six that neutrality was not a stumbling block either to political unity or to membership of a future European defense force. He answered direct queries on this point from the governments of the six EEC states in various speeches around Ireland, in Brussels, and in Dail Eireann. The permanent secretaries of the core Irish government departments worked long and hard to come up with a formula that danced around the politically sensitive question of neutrality but would also satisfy the EEC.
The economies of east Asia have developed thanks to an endless supply of cheap labour, complete disregard for the environment, and advantageous access to raw materials. China and the US have large populations, large land masses, natural resources, and can take advantage of economies of scale. China in particular has been able to take advantage of political goodwill in the US when transforming its communist economy into a more consumer-oriented one. It has also been able to take advantage of political friendliness and primary exports from neighbouring Russia.
Outside of China, and India, there are the ASEAN countries.
ASEAN is a regional intergovernmental organisation comprising ten Southeast Asian states which promotes Pan-Asianism, intergovernmental cooperation and facilitates economic, political, military, educational and cultural integration amongst its members and Asian states. Since its formation on 8 August 1967 by Indonesia, Malaysia, the Philippines, Singapore, and Thailand,[11] the organisation's membership has expanded to include Brunei, Cambodia, Laos, Myanmar, and Vietnam. Its principal aims include accelerating economic growth, social progress, and sociocultural evolution among its members, alongside the protection of regional stability and the provision of a mechanism for member countries to resolve differences peacefully.[12][13] ASEAN is an official United Nations Observer.[14][15] Communication by members across nations takes place in English...
...As set out in the ASEAN Declaration, the aims and purposes of ASEAN are:
<span class="italic">To accelerate economic growth, social progress, and cultural development in the region.</span>
<span class="italic">To promote regional peace and stability.</span>
<span class="italic">To promote collaboration and mutual assistance on matters of common interest.</span>
<span class="italic">To provide assistance to each other in the form of training and research facilities.</span>
<span class="italic">To collaborate for the better utilisation of agriculture and industry to raise the living standards of the people.</span>
<span class="italic">To promote Southeast Asian studies.</span>
<span class="italic">To maintain close, beneficial co-operation with existing international organisations with similar aims and purposes</span>
en.wikipedia.org/wiki/Association_of_Southeast_Asian_Nations
Does any of that sound familiar?
Take a look at the Wiki link and examine the GDP figures for ASEAN states.
While the rest of the world groups itself together, just over half of the UK's voters, seething about the shape of bananas and seduced by lies on the side of a bus, decided to boldly go where no sane state in recent history has gone, alone. As the song goes, 'Freedom's just another word for nothing left to lose'.
Wrt Membership of the EU is not just accepting trade rules, its accepting many more rules and edicts from Brussels how to run the country, and for a country like the UK where less than 15% of our GDP is directly attributed to exporting to the EU – there is clearly so much more of our economy being run by, and no doubt held back, being in an EU so preoccupied with itself.
...and no doubt held back 
Got figures to back that assertion?
Do you have any evidence for that or are you just nostalgic for the heady days when British industry swallowed farmland, blighted the countryside, when mines employed small children, and mills were staffed by women and girls, spinning cotton harvested by slaves in the US and workers paid a pittance in Egypt and India? Do you miss the smogs of the 50s? Take a holiday to China and experience the headlong rush to global dominance that once was the UK's, warts and all.
The EIB is still up and running, but it has recently curtailed lending for important UK infrastructure projects, in light of Brexit.
While the bank also lends to non-EU nations, 90% of loans go to member states. Consideration is being given to the prospect of allowing the UK to remain a member after Brexit, but that would require a change to the bank’s constitution.
The bank has made loans of more than £52bn in the past decade to UK-based projects, including £5.5bn last year supporting schemes such as schools, universities and new hospitals.
The decision of the management board will have an impact on both funding for infrastructure projects and lending by the European Investment Fund, a public-private partnership of which the EIB is a majority shareholder. The EIF accounts for more than a third of investment in UK-based venture capital funds, whose clients include entrepreneurs and creative startups.
A source close to the EIB said: “The decision that was taken by the management board was to continue engagement in the UK, but look carefully to make sure of our long-term investments both on the infrastructure side and equity side, where lending agreed now will continue after the withdrawal date.
www.theguardian.com/politics/2017/may/15/uk-infrastructure-projects-could-be-hit-by-european-investment-bank-concerns
Can you explain why the UK sells so relatively little to the EU? What is holding the UK back?
...............
www.theguardian.com/business/2017/may/15/jp-morgan-landmark-office-dublin-brexit
And would you look at that...