They won't "use" per se, just hodl it like the rest of us, albeit in bigger quantities.
But surely, it will have a positive effect in the long run.

I don't think they will go to such extents to undermine the network that much.

It's a good development for sure, but nothing to worry about.

It is too early to talk about this stage in which countries will enter into a war over Bitcoin because this is theoretically technically almost impossible unless technology develops in the future to allow colonial powers to plunder the resources of colonies in reality and on the Internet as well, or to steal them publicly since it is not difficult to discover this because Bitcoin is not like precious metals that are easy to steal.

It is almost evident that countries competing to collect the largest possible balance of Bitcoin will gradually turn into Bitcoin whales capable of monopolizing the network. In my opinion, no matter how big the whale countries become, there are always other parties that have long started storing Bitcoin that will be able to continue supporting decentralization and always reduce the authority of whales. In my opinion, the fears of who will control mining in the future with the increasing difficulty and increasing cost of investment, which perhaps only countries with huge budgets or some very few companies will be able to do.

I don't think the governments can be the heaviest whales we are going to be having, though we may not include El-Salvador in this, because they were already known for bitcoin investment right from time, but as of now, currently we can't predict on which country is going to accept bitcoin as it's official and legal currency, then also have the same mentality for investing in bitcoin, but since their leader is already showing interest for crypto reserve, let's expect that bitcoin should be the first consideration on this.

Fiat would still be their main way of doing such things, don't worry much 

Or they just may use it to cash out back to their good ol' fiat bags in the end.
 

When do we think the government of each country will see the potential of Bitcoin and buy to hold as reserve? Recall, Trump never liked Bitcoin from day one, he hated it and there records where he said few things until his last day in office, he stand remain the same. Kamala and Biden did the same thing just like they do put the interest of Americans first but because Trump needed to get back to office, he changed his views which might not be the case in other countries.

If they don't like Bitcoin, nothing will make them change their mind. Tbe executive order he has been signing up and down are all the promises he made during his campaign and not to be a liar, he is doing that now but they are not buying any Bitcoin. They/he promised to hold the seized Bitcoin in the last 7 years, that wasn't the promise he made and now everyone is saying "yea he fuck up us up but we will be fine in the end". This is what you get for trusting someone so desperate.

In the past one month, we've seen governments of top global economic countries declare interest in buying Bitcoin in large quantities —the US government which happens to be controlling the largest economy in the world is part of this trend. With the involvement of the US government in buying Bitcoin reserve, I think it'll influence other governments of the world to follow suit and because we know the government have more financial strength to buy more than individuals, it's very likely that governments will become the biggest whales in Bitcoin ownership in no distant time

No country except El Salvador has directly given official legal approval to Bitcoin, so there is no accurate information available about Bitcoin investments in any other country except for the Bitcoin investment of the President of El Salvador. However, other countries that have more reserves than Bitcoin must have some form of confiscated Bitcoin. It is not a country that has invested legally, but rather has confiscated Bitcoin from those who have invested in Bitcoin illegally.