But war will not cause any economic expansion, nor would breaking of the EU, quite the opposite. If you can show how lack of EU would lead to better results, do provide a good and credible analysis, maybe something can be used and salvaged.

Each and every country would face the same problem, separately and with interesting various plans bbut no negotiation position compared to China or Russia or US. Even Germany or France alone would have serious problems negotiating with these economic powers.

Positive action like promoting internal market, good trade deals, subsidizing and making it easier to run manufacturing again, rebalancing from pure services. Pooling resources. It is what EU all offers much better than any individual country could... even then it it's just not enough.

You cannot outmaneuver 3/4 of the planetary manpower ever without a serious technological gap, and that is closing or already has closed. Even with Russian force and resources they will ultimately fail to dominate. US with their remaining tech lead is already failing...